Editing Constantine II of Scotland

{{Short description|King of Alba from 900 to 943}}
{{featured article}}
{{Use British English|date=October 2013}}
{{Use dmy dates|date=July 2024}}
{{Infobox royalty
| name            = Constantine II
| image           = Constantine II, King of Scotland.jpg
| caption         = Fictional 17th-century drawing
| succession      = [[King of Alba (Scotland)]]
| reign           = April 900 – 943
| predecessor     = [[Donald II]]
| successor       = [[Malcolm I]]
| birth_date      = no later than 879
| death_date      = {{death year and age|952|878}}
| death_place     = [[St Andrews]], Scotland
| issue           = [[Indulf]], King of Alba<br />Cellach<br />one or more daughters
| house           = [[House of Alpin|Alpin]]
| father          = [[Áed of Scotland|Áed]], King of the Picts
| place of burial = [[Iona]]
}}

'''Causantín mac Áeda''' ([[Scottish Gaelic language|Modern Gaelic]]: {{lang|gd|Còiseam mac Aoidh}}, [[anglicised]] '''Constantine II'''; born no later than 879; died 952) was an early [[List of Scottish monarchs|King of Scotland]], known then by the Gaelic name ''Alba''. The [[Kingdom of Alba]], a name which first appears in Constantine's lifetime, was situated in what is now [[Northern Scotland]].

The core of the kingdom was formed by the lands around the [[River Tay]]. Its southern limit was the [[River Forth]], northwards it extended towards the [[Moray Firth]] and perhaps to [[Caithness]], while its western limits are uncertain. Constantine's grandfather [[Kenneth I]] (Cináed mac Ailpín, died 858) was the first of the family recorded as a king, but as [[king of the Picts]]. This change of title, from king of the Picts to [[king of Alba]], is part of a broader transformation of [[Pictland]] and the [[origins of the Kingdom of Alba]] are traced to Constantine's lifetime.

His reign, like those of his predecessors, was dominated by the actions of Norse rulers in the [[British Isles]], particularly the [[Uí Ímair]] ('Grandsons/Descendants of Ímar', or [[Ivar the Boneless]]). During Constantine's reign, the rulers of the southern kingdoms of [[Wessex]] and [[Mercia]], later the [[Kingdom of England]], extended their authority northwards into the disputed kingdoms of [[Northumbria]]. At first, the southern rulers allied with him against the Vikings, but in 934, Æthelstan, unprovoked, invaded Scotland both by sea and land with a huge host that included four [[Wales in the early Middle Ages|Welsh kings]]. He ravaged southern Alba, but there is no record of any battles. He had withdrawn by September. Three years later, in 937, probably in retaliation for the invasion of Alba, King Constantine allied with [[Olaf Guthfrithson]], [[King of Dublin]], and [[Owain ap Dyfnwal (fl. 934)|Owain ap Dyfnwal]], [[King of Strathclyde]], but they were defeated at the [[battle of Brunanburh]]. In 943, Constantine abdicated the throne and retired to the [[Céli Dé]] (Culdee) [[Church of St Mary on the Rock|monastery of St Andrews]] where he died in 952. He was succeeded by his predecessor's son [[Malcolm I]] ([[Máel Coluim mac Domnaill]]).

Constantine's reign of 43 years, exceeded in Scotland only by that of King [[William the Lion]] before the [[Union of the Crowns]] in 1603, is believed to have played a defining part in the [[Gaelicisation]] of [[Pictland]], in which his patronage of the Irish Céli Dé monastic reformers was a significant factor. During his reign, the words "Scots" and "Scotland" ({{langx|ang|Scottas, Scotland}}) were first used to mean part of what is now [[Scotland]]. The earliest evidence for the ecclesiastical and administrative institutions which would last until the [[Davidian Revolution]] also appears at this time.

== Sources ==
Compared to neighbouring [[Ireland]] and [[Anglo-Saxon England]], few records of 9th and 10th century events in Scotland survive. The main local source from the period is the ''[[Chronicle of the Kings of Alba]]'', a list of kings from Kenneth MacAlpin (died 858) to [[Kenneth II]] ([[Cináed mac Maíl Coluim]], died 995). The list survives in the [[Poppleton manuscript]], a 13th-century compilation. Originally simply a list of kings with reign lengths, the other details contained in the Poppleton manuscript version were added in the 10th and 12th centuries.<ref>Woolf, ''Pictland to Alba'', pp. 87–93; Dumville, "Chronicle of the Kings of Alba".</ref> In addition to this, later king lists survive.<ref>Anderson, ''Kings and Kingship'', reproduces these lists and discusses their origins.</ref> The earliest [[Genealogy|genealogical records]] of the descendants of [[Kenneth MacAlpin]] may date from the end of the 10th century, but their value lies more in their context, and the information they provide about the interests of those for whom they were compiled, than in the unreliable claims they contain.<ref>Broun, ''Irish Identity'', pp. 133–164; Woolf, ''Pictland to Alba'', pp. 220–221.</ref>

For narrative history, the principal sources are the ''[[Anglo-Saxon Chronicle]]'' and the [[Irish annals]]. The evidence from [[charter]]s created in the [[Kingdom of England]] provides occasional insight into events in Scotland.<ref>Woolf, ''Pictland to Alba'', pp. 2–3, 87–88, 357–359.</ref> While [[Scandinavia]]n [[sagas]] describe events in 10th century Britain, their value as sources of historical narrative, rather than documents of social history, is disputed.<ref>Woolf, ''Pictland to Alba'', pp. 277–285; Ó Corrain, "Vikings in Scotland and Ireland"; Sawyer and Sawyer, ''Medieval Scandinavia'', pp. 21–26.</ref> Mainland European sources rarely concern themselves with affairs in any part of the [[British Isles]], and even less commonly with events in Scotland, but the life of Saint [[Cathróe of Metz]], a work of [[hagiography]] written in [[Germany]] at the end of the 10th century, provides plausible details of the saint's early life in north Britain.<ref>MacQuarrie, ''Saints of Scotland'', pp. 199–210.</ref>

While the sources for north-eastern Britain, the lands of the [[kingdom of Northumbria]] and the [[Picts|former Pictland]], are limited and late, those for the areas on the [[Irish Sea]] and Atlantic coasts — the modern regions of north-west England and all of northern and western Scotland — are non-existent, and [[archaeology]] and [[toponymy]] are of primary importance.<ref>Woolf, ''Pictland to Alba'', p. 12.</ref>

== Pictland from Constantín mac Fergusa to Constantine I ==
{{main|Origins of the Kingdom of Alba}}
[[Image:Early Alpinid kings.svg|280px|thumb|Recorded relationships within the early [[House of Alpin]]]]

The dominant kingdom in eastern Scotland before the [[Viking Age]] was the northern [[List of kings of the Picts|Pictish kingdom]] of [[Fortriu]] on the shores of the [[Moray Firth]]. By the 9th century, the [[Gaels]] of [[Dál Riata]] (Dalriada) were subject to the kings of Fortriu of the family of [[Causantín mac Fergusa]] (Constantine son of Fergus). Constantín's family dominated Fortriu after 789 and perhaps, if Constantín was a kinsman of [[Óengus I of the Picts]] (Óengus son of Fergus), from around 730. The dominance of Fortriu came to an end in 839 with a defeat by Viking armies reported by the ''[[Annals of Ulster]]'' in which King [[Eóganan mac Óengusa|Uen]] of Fortriu and his brother Bran, Constantín's nephews, together with the [[king of Dál Riata]], [[Áed mac Boanta]], "and others almost innumerable" were killed.<ref>''Annals of Ulster'', s.a. 838.</ref> These deaths led to a period of instability lasting a decade as several families attempted to establish their dominance in Pictland. By around 848 [[Kenneth MacAlpin]] had emerged as the winner.<ref>Woolf, ''Pictland to Alba'', pp. 57–67, 93–98; Smyth, ''Warlords and Holy Men'', pp. 180–185; Duncan, ''Kingship of the Scots'', pp. 8–10; Bannerman, "Scottish takeover"; Foster, ''Picts, Gaels and Scots'', pp. 107–108.</ref>

Later [[national myth]] made Kenneth MacAlpin the creator of the [[Kingdom of Scotland]], the founding of which was dated from 843, the year in which he was said to have destroyed the [[Picts]] and inaugurated a new era. The historical record for 9th century Scotland is meagre, but the Irish annals and the 10th century ''Chronicle of the Kings of Alba'' agree that Kenneth was a Pictish king, and call him "king of the Picts" at his death. The same style is used of Kenneth's brother [[Donald I]] (Domnall mac Ailpín) and sons [[Causantín mac Cináeda|Constantine I]] (Constantín mac Cináeda) and [[Áed mac Cináeda|Áed]] (Áed mac Cináeda).<ref>Woolf, ''Pictland to Alba'', pp. 93–117, 320–322; Broun, "Dunkeld"; Duncan, ''Kingship of the Scots'', pp. 13–14; Herbert, "''Ri Éirenn, Ri Alban''"; Dumville, "Chronicle of the Kings of Alba", p. 76.</ref>

The kingdom ruled by Kenneth's descendants — older works used the name [[House of Alpin]] to describe them but descent from Kenneth was the defining factor, Irish sources referring to ''Clann Cináeda meic Ailpín'' ("the Clan of Kenneth MacAlpin")<ref>Woolf, ''Pictland to Alba'', pp. 220–221, 256–257; Broun, ''Irish Identity'', pp. 173–174</ref> — lay to the south of the previously dominant kingdom of Fortriu, centred in the lands around the [[River Tay]]. The extent of Kenneth's nameless kingdom is uncertain, but it certainly extended from the [[Firth of Forth]] in the south to the [[Mounth]] in the north. Whether it extended beyond the mountainous spine of north Britain — [[Druim Alban]] — is unclear. The core of the kingdom was similar to the old counties of [[Kincardineshire|Mearns]], [[Forfarshire]], [[Forfar]], [[Perthshire|Perth]], [[Fife]], and [[Kinross-shire|Kinross]]. Among the chief ecclesiastical centres named in the records are [[Dunkeld]], probably the seat of the bishop of the kingdom, and ''Cell Rígmonaid'' (modern [[St Andrews]]).<ref>Woolf, ''Pictland to Alba'', pp. 98–101; Driscoll, ''Alba'' pp. 33–51; Foster, ''Picts, Gaels and Scots'', pp. 8 fig. 1, 39 fig. 24, 110–111.</ref>

Kenneth's son Constantine died in 876, probably killed fighting against a Viking army that had come north from Northumbria in 874. According to the king lists, he was counted as the 70th and last king of the Picts in later times.<ref>Woolf, ''Pictland to Alba'', pp. 106–116; Swanton, ''Anglo-Saxon Chronicle'', pp. 72–75, s.a. 875. For Constantine as the last Pictish king, the original count being 66 kings, see Woolf, ''Pictland to Alba'', pp. 124–126; Broun, ''Irish Identity'', pp. 168–169; Anderson, ''Kings and Kingship'', pp. 78–79.</ref>

== Britain and Ireland at the end of the 9th century ==
[[Image:Locations in north Britain in the early tenth century.png|thumb|Some locations in northern Britain, late 9th and early 10th centuries. The dotted line marked A represents the southern boundary of the [[Kingdom of Alba]], {{circa}} 890–950. The dotted line marked B represents the southern boundary of the [[Kingdom of Strathclyde]], c. 925–945.]]

In 899 [[Alfred the Great]], king of [[Wessex]], died leaving his son [[Edward the Elder]] as ruler of England south of the [[River Thames]] and his daughter [[Æthelflæd]] and son-in-law [[Æthelred, Lord of the Mercians|Æthelred]] ruling the western, English part of [[Mercia]]. The situation in the [[Danish Realm|Danish kingdoms]] of eastern England is less clear. King [[Eohric of East Anglia|Eohric]] was probably ruling in [[East Anglia]], but no dates can reliably be assigned to the successors of [[Guthred|Guthfrith of York]] in [[Northumbria]]. It is known that Guthfrith was succeeded by [[Siefredus of Northumbria|Siefredus]] and [[Cnut of Northumbria|Cnut]], although whether these men ruled jointly or one after the other is uncertain. Northumbria may have been divided by this time between the Viking kings in York and the local rulers, perhaps represented by [[Eadwulf I of Bamburgh|Eadulf]], based at [[Bamburgh]] who controlled the lands from the [[River Tyne]] or [[River Tees]] to the [[river Forth|Forth]] in the north.<ref>Keynes, "Rulers of the English", pp. 504–505; Woolf, ''Pictland to Alba'', pp. 138–139; Blair, ''Anglo-Saxon England'', pp. 75–79.</ref>

In [[Ireland]], [[Flann Sinna]], married to Constantine's aunt [[Máel Muire ingen Cináeda|Máel Muire]], was dominant. The years around 900 represented a period of weakness among the Vikings and [[Norse–Gaels]] of [[Dublin]]. They are reported to have been divided between two rival leaders. In 894 one group left Dublin, perhaps settling on the Irish Sea coast of Britain between the [[River Mersey]] and the [[Firth of Clyde]]. The remaining Dubliners were expelled in 902 by Flann Sinna's son-in-law [[Cerball mac Muirecáin]], and soon afterwards appeared in western and northern Britain.<ref>Annals of Ulster, s.a. 893 and 902; Woolf, ''Pictland to Alba'', pp 131, 138–139.</ref>

To the southwest of Constantine's lands lay the [[Kingdom of Strathclyde]]. This extended north into [[The Lennox]], east to the River Forth, and south into the [[Southern Uplands]]. In 900 it was probably ruled by King [[Dyfnwal, King of Strathclyde|Dyfnwal]].<ref>Woolf, ''Pictland to Alba'', pp. 153–157.</ref>

The situation of the [[List of Irish kingdoms|Gaelic kingdoms]] of [[Dál Riata]] in western Scotland is uncertain. No kings are known by name after [[Áed mac Boanta]]. The [[Francia|Frankish]] ''[[Annales Bertiniani]]'' may record the conquest of the [[Inner Hebrides]], the seaward part of Dál Riata, by Northmen in 849.<ref>Woolf, pp. 99–100, 286–289; Anderson, ''Early Sources'', p. 277.</ref> In addition to these, the arrival of new groups of Vikings from northern and western Europe was still commonplace. Whether there were Viking or Norse-Gael kingdoms in the [[Western Isles]] or the [[Northern Isles]] at this time is debated.<ref>Woolf, ''Pictland to Alba'', pp. 275–311, especially 286–289; Ó Corrain, "Vikings in Scotland and Ireland"; Crawford, ''Scandinavian Scotland'', pp. 39–62; Smyth, ''Warlords and Holy Men'', pp. 141–174.</ref>

== Early life ==
[[Áed mac Cináeda|Áed]], Constantine's father, succeeded Constantine's uncle and namesake [[Causantín mac Cináeda|Constantine I]] in 876 but was killed in 878. Áed's short reign is glossed as being of no importance by most king lists. Although the date of his birth is nowhere recorded, Constantine II cannot have been born any later than the year after his father's death, ''i.e.'', 879. His name may suggest that he was born a few years earlier, during the reign of his uncle Constantine I.<ref>Woolf, ''Pictland to Alba'', pp. 116–117, 124, and 166, note 84.</ref>

After Áed's death, there is a two-decade gap until the death of [[Donald II]] (Domnall mac Constantín) in 900 during which nothing is reported in the Irish annals.<ref>Anderson, ''Early Sources'', pp. 357–358, 395; Woolf, ''Pictland to Alba'', pp. 117–118.</ref> The entry for the reign between Áed and Donald II is corrupt in the ''Chronicle of the Kings of Alba'', and in this case, the ''Chronicle'' is at variance with every other king list.<ref>On this, note Dumville's comments regarding [[damnatio memoriae]], Dumville, "Chronicle of the Kings of Alba", p. 75; see also Woolf, ''Pictland to Alba'', pp. 117–121.</ref> According to the ''Chronicle'', Áed was followed by [[Eochaid of Scotland|Eochaid]], a grandson of Kenneth MacAlpin, who is somehow connected with [[Giric]], but all other lists say that Giric ruled after Áed and make great claims for him.<ref>Anderson, ''Kings and Kingship'', pp. 251–252, 254, 263, 267, 274, 283 and 288.</ref> Giric is not known to have been a kinsman of Kenneth's, although it has been suggested that he was related to him by marriage. The major changes in Pictland which began at about this time have been associated by [[Alex Woolf]] and [[Archie Duncan (historian)|Archie Duncan]] with Giric's reign.<ref>Duncan, pp. 11–16; Woolf, ''Pictland to Alba'', pp. 117–121, 137–138 and 320–322. For an alternative view of all this, see Smyth, ''Warlords and Holy Men'', pp. 215–218.</ref>

Woolf suggests that Constantine and his younger brother Donald may have passed Giric's reign in exile in Ireland where their aunt Máel Muire was wife of two successive [[High Kings of Ireland]], [[Áed Findliath]] and [[Flann Sinna]].<ref>Woolf, ''Pictland to Alba'', pp. 122–125.</ref> Giric died in 889. If he had been in exile, Constantine may have returned to Pictland where his cousin Donald II became king. Donald's reputation is suggested by the [[epithet]] ''dasachtach'', a word used of violent madmen and mad bulls, attached to him in the 11th-century writings of [[Flann Mainistrech]], echoed by his description in ''[[The Prophecy of Berchán]]'' as "the rough one who will think relics and psalms of little worth".<ref>Anderson, ''Early Sources'', pp. cxlix and 397–398.</ref> Wars with the Viking kings in Britain and Ireland continued during Donald's reign and he was probably killed fighting yet more Vikings at [[Dunnottar]] in the [[Mearns (ward)|Mearns]] in 900. Constantine succeeded him as king.<ref>Woolf, p. 125; Anderson, ''Early Sources'', pp. 395–398. The account of the conquest of the [[Kingdom of Strathclyde]] in Domnall's time given by, for example, Smyth, ''Warlords and Holy Men'', pp. 217–218, is rejected by Duncan, ''Kingship of the Scots'', p. 40, and Woolf, ''Pictland to Alba'', pp. 152–157.</ref>

== Vikings and bishops ==
[[File:NMSMonymuskReliquary2.jpg|thumb|The cult of Saint [[Columba]] and its relics were associated with victory in battle. The ''Cathbuaid'', Columba's [[crozier]] or staff, has been lost but the 8th century ''Breccbennach'' or [[Monymusk Reliquary]] shown here, which held relics of Columba, is known to have been carried into battle from the reign of King [[William the Lion]] onwards.<ref>Yorke, ''The Conversion of Britain'', pp. 190–191; Alcock, ''Kings and Warriors'', pp. 327–329; Smyth, ''Warlords and Holy Men'', p.136. See also the [[Cathach of St. Columba]], a 7th century [[psalter]] to which similar powers were attributed.</ref>]]

The earliest event recorded in the ''[[Chronicle of the Kings of Alba]]'' in Constantine's reign is an attack by Vikings and the plundering of [[Dunkeld]] "and all Albania" in his third year. This is the first use of the word Albania, the [[Latin]] form of the [[Old Irish]] ''Alba'', in the ''Chronicle'' which until then describes the lands ruled by the descendants of Cináed as Pictavia.<ref>Woolf, ''Pictland to Alba'', pp. 122–126; Anderson, ''Early Sources'', pp. 444–446, where Albania is translated as Scotland; Broun, "Dunkeld".</ref>

These Norsemen could have been some of those who were driven out of [[Dublin]] in 902 or were the same group who had defeated Domnall in 900. The ''Chronicle'' states that the Northmen were killed in ''Srath Erenn'', which is confirmed by the ''Annals of Ulster'' which records the death of [[Ímar ua Ímair|Ímar grandson of Ímar]] and many others at the hands of the men of Fortriu in 904. This Ímar was the first of the [[Uí Ímair]], the grandsons of Ímar, to be reported; three more grandsons of Ímar appear later in Constantín's reign. The ''[[Fragmentary Annals of Ireland]]'' contain an account of the battle, and this attributes the defeat of the Norsemen to the intercession of Saint [[Columba]] following fasting and prayer. An entry in the ''[[Chronicon Scotorum]]'' under the year 904 may possibly contain a corrupted reference to this battle.<ref>Woolf, ''Pictland to Alba'', pp. 127–128, 130–131; Anderson, ''Early Sources'', pp. 398, 399, 444–446; ''Annals of Ulster'', s.a. 902, 904; ''Chronicon Scotorum'', s.a. 902, 904; ''Fragmentary Annals'', FA 429.</ref>

The next event reported by the ''Chronicle of the Kings of Alba'' is dated to 906. This records that:
{{blockquote|King Constantine and Bishop [[Cellach I|Cellach]] met at the ''Hill of Belief'' near the royal city of [[Scone, Scotland|Scone]] and pledged themselves that the laws and disciplines of the faith, and the laws of churches and gospels, should be kept ''pariter cum Scottis''.<ref>After Anderson, ''Early Sources'', p. 445.</ref>}} The meaning of this entry, and its significance, have been the subject of debate.

[[Image:Moot hill.jpg|thumb|left|The [[moot hill]] at Scone, perhaps the ''Hill of Belief'' of 906<ref>Bannerman, "Scottish Takeover", p. 79.</ref>]]

The phrase ''pariter cum Scottis'' in the [[Latin]] text of the ''Chronicle'' has been translated in several ways. [[William Forbes Skene]] and [[Alan Orr Anderson]] proposed that it should be read as "in conformity with the customs of the Gaels", relating it to the claims in the king lists that Giric liberated the church from secular oppression and adopted Irish customs.<ref>Anderson, ''Early Sources'', p. 445, note 1; Woolf, ''Pictland to Alba'', p. 135. This version is followed by Smyth, ''Warlords and Holy Men'', pp. 188–189.</ref> It has been read as "together with the Gaels", suggesting either public participation or the presence of Gaels from the western coasts as well as the people of the east coast.<ref>Driscoll, p. 37, translates the phrase in this way; Woolf, ''Pictland to Alba'', pp. 135–136.</ref> Finally, it is suggested that it was the ceremony that followed "the custom of the Gaels" and not the agreements.<ref>Woolf, ''Pictland to Alba'', p. 136; see also Smyth, ''Warlords and Holy Men'', p. 188.</ref>

The idea that this gathering agreed to uphold Irish laws governing the church has suggested that it was an important step in the [[gaelicisation]] of the lands east of Druim Alban.<ref>Smyth, ''Warlords and Holy Men'', pp. 188–189, writes that "it marks the final triumph of the Gaelic order over the old Pictish order".</ref> Others have proposed that the ceremony in some way endorsed Constantine's kingship, prefiguring later royal inaugurations at Scone.<ref>Driscoll, ''Alba'', p. 37; Duncan, ''Kingship of the Scots'', pp. 15–16.</ref> Alternatively, if Bishop Cellach was appointed by Giric, it may be that the gathering was intended to heal a rift between king and church.<ref>Woolf, ''Pictland to Alba'', pp. 137–138.</ref>

== Return of the Uí Ímair ==
Following the events at Scone, there is little of substance reported for a decade. A story in the ''Fragmentary Annals of Ireland'', perhaps referring to events sometime after 911, claims that [[Æthelflæd]], who ruled in [[Mercia]], allied with the [[Irish people|Irish]] and northern rulers against the Norsemen on the Irish sea coasts of [[Northumbria]]. The ''Annals of Ulster'' record the defeat of an Irish fleet from the kingdom of [[Ulaid]] by Vikings "on the coast of England" at about this time.<ref>Higham, ''Kingdom of Northumbria'', pp. 185–186; ''Fragmentary Annals of Ireland'', FA 429; ''Annals of Ulster'', s.a. 913.</ref>

In this period the ''Chronicle of the Kings of Alba'' reports the death of [[Cormac mac Cuilennáin]], [[king of Munster]], in the eighth year of Constantine's reign.<ref>The ''Annals of Ulster'' states that Cormac died on {{Nowrap|13 September}} 908; Woolf, pp. 127–129.</ref> This is followed by an undated entry which was formerly read as "In his time Domnall [i.e. Dyfnwal], king of the [Strathclyde] Britons died, and Domnall son of Áed was elected". This was thought to record the election of a brother of Constantine named Domnall to the kingship of the Britons of Strathclyde and was seen as early evidence of the domination of Strathclyde by the kings of Alba. The entry in question is now read as "... Dyfnwal ... and Domnall son Áed [[king of Ailech]] died", this [[Domnall mac Áeda|Domnall]] being a son of [[Áed Findliath]] who died on 21 March 915.<ref>Domnall's death is recorded by the ''Annals of Ulster''. For the re-reading by Benjamin Hudson, see Woolf, ''Pictland to Alba'', pp. 127–129, 152–157; Dumville, "Chronicle of the Kings of Alba", p. 77. Smyth, ''Warlords and Holy Men'', pp. 222–223, is typical of the interpretation found in older works. The phrase in question reads "''et Dunenaldus filius Ede elig<sub>7</sub>''".</ref> Finally, the deaths of [[Flann Sinna]] and [[Niall Glúndub]] are recorded.<ref>The ''Annals of Ulster'' record the death of Flann on 25 May 916 and that of Niall on 14 September 919; Woolf, pp. 127–129.</ref>

There are more reports of Viking fleets in the [[Irish Sea]] from 914 onwards. By 916 fleets under [[Sihtric Cáech]] and [[Ragnall ua Ímair|Ragnall]], said to be grandsons of Ímar (that is, they belonged to the same [[Uí Ímair]] kindred as the Ímar who was killed in 904), were very active in [[Ireland]]. Sihtric inflicted a heavy defeat on the armies of [[Leinster]] and retook Dublin in 917.<ref>Hart, "Sihtric Cáech"; Hart "Ragnall"; Woolf, ''Pictland to Alba'', pp. 138–141; ''Annals of Ulster'', s.a. 914–917.</ref> The following year Ragnall appears to have returned across the Irish Sea intent on establishing himself as king at [[York]].<ref>Woolf, ''Pictland to Alba'', p. 142; ''Annals of Ulster'', s.a. 918.</ref> The only precisely dated event in the summer of 918 is the death of Æthelflæd of Mercia on 12 June 918 at [[Tamworth, Staffordshire]]. Æthelflæd had been negotiating with the Northumbrians to obtain their submission, but her death put an end to this and her successor, her brother [[Edward the Elder]], was occupied with securing control of [[Mercia]].<ref>Higham, ''Kingdom of Northumbria'', pp. 186–188; Swanton, ''Anglo-Saxon Chronicle'', p. 105, Ms. C, s.a. 918, 919.</ref>

[[Image:Dere Street.JPG|thumb|[[Dere Street]]; Corbridge is just south of [[Hadrian's Wall]] in the centre of the map]]

The northern part of [[Northumbria]], and perhaps the whole kingdom, had probably been ruled by [[Ealdred I of Bamburgh|Ealdred]] son of [[Eadwulf I of Bamburgh|Eadulf]] since 913.<ref>Keynes, "Rulers of the English"; Woolf, ''Pictland to Alba'', pp. 138–141.</ref> Faced with Ragnall's invasion, Ealdred came north seeking assistance from Constantine. The two advanced south to face Ragnall, and this led to a battle somewhere on the banks of the [[River Tyne]], probably at [[Corbridge]] where [[Dere Street]] crosses the river. The [[Battle of Corbridge]] appears to have been indecisive; the ''Chronicle of the Kings of Alba'' is alone in giving Constantine the victory.<ref>There is disagreement as to whether there was one battle at Corbridge in the 910s or two. The ''Annals of Ulster'', s.a. 918, the ''Fragmentary Annals of Ireland'', and the ''Chronicle of the Kings of Alba'', report only one battle. The idea that there were two rests on the ''[[Historia de Sancto Cuthberto]]'', for which see Anderson, ''Scottish Annals'', p. 64. The question is discussed by Woolf, ''Pictland to Alba'', pp. 142–144; Stenton, ''Anglo-Saxon England'', pp. 332–333.</ref>

The report of the battle in the ''Annals of Ulster'' says that none of the kings or [[mormaer]]s among the men of Alba were killed. This is the first surviving use of the word mormaer; other than the knowledge that Constantine's kingdom had its own bishop or bishops and royal villas, this is the only hint to the institutions of the kingdom.<ref>For Mormaers, see Woolf, ''Pictland to Alba'', pp 342–350; Smyth, ''Warlords and Holy Men'', pp. 219–220. For the later institutions of the kingdom of Alba, see {{citation |last=Barrow |first=G. W. S. |author-link=G. W. S. Barrow |title=The Kingdom of the Scots. Government, Church and Society from the eleventh to the fourteenth century |edition=2nd |year=2003 |location=Edinburgh |publisher=[[Edinburgh University Press]] |isbn=0-7486-1803-1 |pages=1–67}}</ref>

After Corbridge, Ragnall enjoyed only a short respite. In the south, Alfred's son Edward had rapidly secured control of Mercia and had a [[burh]] constructed at [[Bakewell]] in the [[Peak District]] from which his armies could easily strike north. An army from [[Dublin]] led by Ragnall's kinsman Sihtric struck at north-western Mercia in 919, but in 920 or 921 Edward met with Ragnall and other kings. The ''Anglo-Saxon Chronicle'' states that these kings "chose Edward as father and lord". Among the other kings present were Constantine, Ealdred son of Eadwulf, and the king of Strathclyde, [[Owain ap Dyfnwal (fl. 934)|Owain ap Dyfnwal]]. Here, again, a new term appears in the record, the ''Anglo-Saxon Chronicle'' for the first time using the word ''scottas'', from which Scots derives, to describe the inhabitants of Constantine's kingdom in its report of these events.<ref>Stenton, ''Anglo-Saxon England'', pp. 333–335; Swanton, ''Anglo-Saxon Chronicle'', p. 104, Ms. A, s.a. 924; Woolf, ''Pictland to Alba'', pp. 145–147.</ref>

Edward died in 924. His realms appear to have been divided with the West Saxons recognising [[Ælfweard of Wessex|Ælfweard]] while the Mercians chose [[Æthelstan]] who had been raised at Æthelflæd's court. Ælfweard died within weeks of his father and Æthelstan was inaugurated as king of all of Edward's lands in 925.<ref>Keynes, "Rulers of the English", p. 514; Miller, "Æthelstan"; Stenton, ''Anglo-Saxon England'', p. 339.</ref>

== Æthelstan ==
{{see also|Æthelstan's invasion of Scotland}}

By 926 Sihtric had evidently acknowledged [[Æthelstan]] as overlord, adopting [[Christianity]] and marrying a sister of Æthelstan at [[Tamworth, Staffordshire|Tamworth]]. Within the year he appears to have forsaken his new faith and repudiated his wife, but before Æthelstan could respond, Sihtric died suddenly in 927. His kinsman, perhaps brother, [[Gofraid ua Ímair|Gofraid]], who had remained as his deputy in [[Dublin]], came from [[Ireland]] to take power in [[York]] but failed. Æthelstan moved quickly, seizing much of [[Northumbria]]. In less than a decade, the [[kingdom of the English]] had become by far the greatest power in Britain and Ireland, perhaps stretching as far north as the [[Firth of Forth]].<ref>Higham, ''Kingdom of Northumbria'', pp. 186–190; Stenton, ''Anglo-Saxon England'', pp. 339–340; Woolf, ''Pictland to Alba'', pp.148–151; Swanton, ''Anglo-Saxon Chronicle'', pp. 105 and 107, Ms. D, s.a. 925, 926, Ms. E, F, s.a. 927.</ref>

John of Worcester's chronicle suggests that Æthelstan faced opposition from Constantine, [[Owain ap Dyfnwal (fl. 934)|Owain]], and the Welsh kings. [[William of Malmesbury]] writes that Gofraid, together with Sihtric's young son [[Olaf Cuaran]] fled north and received refuge from Constantine, which led to war with Æthelstan. A meeting at [[Eamont Bridge]] on 12 July 927 was sealed by an agreement that Constantine, Owain, [[Hywel Dda]], and Ealdred would "renounce all idolatry": that is, they would not ally with the Viking kings. William states that Æthelstan stood godfather to a son of Constantine, probably [[Indulf]] ([[Ildulb mac Constantín]]), during the conference.<ref>Anderson, ''Scottish Annals'', pp. 66–67; Swanton, ''Anglo-Saxon Chronicle'', p.107, Ms. D, s.a. 926; Stenton, ''Anglo-Saxon England'', pp. 339–340; Woolf, ''Pictland to Alba'', pp 150–152, 192–193; Smyth, ''Warlords and Holy Men'', pp. 201–202; Miller, "Æthelstan".</ref>

Æthelstan followed up his advances in the north by securing the recognition of the Welsh kings.<ref>Stenton, ''Anglo-Saxon England'', pp. 340–341.</ref> For the next seven years, the record of events in the north is blank. Æthelstan's court was attended by the Welsh kings, but not by Constantine or Owain. This absence of record means that Æthelstan's reasons for marching north against Constantine in 934 are unclear.<ref>Woolf, ''Pictland to Alba'', pp. 161–165. The previous year had seen the death of Æthelstan's brother [[Edwin (son of Edward the Elder)|Edwin]], perhaps drowned on the king's orders; Swanton, ''Anglo-Saxon Chronicle'', p. 107, Ms. E, s.a. 933 and note 11; Stenton, ''Anglo-Saxon England'', pp. 355–356. The following year Gofraid died and was succeeded by his son Amlaíb, Constantine's son-in-law; ''Annals of Ulster'', s.a. 934. Finally, the ''Annals of Clonmacnoise'' report the death of "Adulf mcEtulfe, king of the North Saxons" in the same year as Æthelstan's campaign; Woolf suggests that this represents Ealdred, or some other son of Eadulf, ruling in Northumbria.</ref>

Æthelstan's invasion is reported in brief by the ''Anglo-Saxon Chronicle'', and later chroniclers such as [[John of Worcester]], [[William of Malmesbury]], [[Henry of Huntingdon]] and [[Symeon of Durham]] add detail to that bald account. Æthelstan's army began gathering at [[Winchester]] by 28 May 934 and travelled north to [[Nottingham]] by 7 June. He was accompanied by many leaders, including the [[Wales in the early Middle Ages|Welsh kings]] [[Hywel Dda]], [[Idwal Foel]] and [[Morgan ab Owain]]. From Mercia, the army continued to [[Chester-le-Street]], before resuming the march accompanied by a fleet of ships. Owain was defeated and Symeon states that the army went as far north as [[Dunnottar]] and [[Fortriu]], while the fleet is said to have raided [[Caithness]], by which a much larger area, including [[Sutherland]], is probably intended. It is unlikely that Constantine's personal authority extended so far north, so the attacks were probably directed at his allies, comprising simple looting expeditions.<ref>Swanton, ''Anglo-Saxon Chronicle'', p. 107, Ms. D, s.a. 934; Anderson, ''Scottish Annals'', pp. 67–69; Miller, "Æthelstan"; Stenton, ''Anglo-Saxon England'', p. 342; Woolf, ''Pictland to Alba'', pp. 160–166; Smyth, ''Warlords and Holy Men'', p. 203.</ref>

The ''[[Annals of Clonmacnoise]]'' state that "the Scottish men compelled [Æthelstan] to return without any great victory", while Henry of Huntingdon claims that the English faced no opposition. A negotiated settlement might have ended matters: according to John of Worcester, a son of Constantine was given as a hostage to Æthelstan and Constantine himself accompanied the English king on his return south. He witnessed a charter with Æthelstan at [[Buckingham]] on 13 September 934 in which he is described as ''subregulus'', ''i.e.'', a king acknowledging Æthelstan's overlordship, the only place there is any record of such a description.<ref>Anderson, ''Early Sources'', p. 426; Anderson, ''Scottish Annals'', pp. 67–69; Woolf, ''Pictland to Alba'', pp. 166–168; {{cite web|url=http://www.anglo-saxons.net/hwaet/?do=get&type=charter&id=426 |title=Charter S 426 |last=Miller |first=Sean |work=Anglo-Saxons.net |access-date=28 November 2007}}</ref> However, there is no record of Constantine having ever submitted to Æthelstan's overlordship or that he considered himself such. The following year, Constantine was again in England at Æthelstan's court, this time at [[Cirencester]] where he appears as a witness, as the first of several kings, followed by Owain and Hywel Dda, who subscribed to the diploma.<ref>Woolf, ''Pictland to Alba'', pp. 166–168; only a part of this charter survives, see {{cite web |url=http://www.trin.cam.ac.uk/kemble/pelteret/Lsp/Lsp%2011.htm |access-date=28 November 2007 |title=Charter S 1792 |work=Anglo-Saxon Charters Website |url-status=dead |archive-url=https://web.archive.org/web/20090227002745/http://www.trin.cam.ac.uk/kemble/pelteret/Lsp/Lsp%2011.htm |archive-date=27 February 2009}}</ref> At Christmas of 935, Owain was once more at Æthelstan's court along with the Welsh kings, but Constantine was not. His return to England less than two years later would be in very different circumstances.<ref>Woolf, ''Pictland to Alba'', pp. 167–168.</ref>

== Brunanburh and after ==
Following his departure from Æthelstan's court after 935, there is no further report of Constantine until 937. In that year, together with Owain and [[Olaf Guthfrithson]] of [[Dublin]], Constantine invaded England. The resulting [[battle of Brunanburh]] — ''Dún Brunde'' — is reported in the ''Annals of Ulster'' as follows:
{{blockquote|a great battle, lamentable and terrible was cruelly fought... in which fell uncounted thousands of the Northmen. ... And on the other side, a multitude of Saxons fell; but Æthelstan, the king of the Saxons, obtained a great victory.<ref>Anderson, ''Early Sources'', pp. 428–429; ''Annals of Ulster'', s.a. 937.</ref>}} The battle was remembered in England a generation later as "the Great Battle". When reporting the battle, the ''Anglo-Saxon Chronicle'' abandons its usual terse style in favour of a heroic poem vaunting the great victory. In this, the "hoary" Constantine, by now around 60 years of age, is said to have lost a son in the battle, a claim which the ''Chronicle of the Kings of Alba'' confirms. The ''Annals of Clonmacnoise'' give his name as Cellach. For all its fame, the site of the battle is uncertain and several sites have been advanced, with [[Bromborough]] on the [[Wirral Peninsula|Wirral]] the most favoured location.<ref>Swanton, ''Anglo-Saxon Chronicle'', pp. 106–110, Ms. A, s.a. 937; Anderson, ''Scottish Annals'', pp. 69–73; Anderson, ''Early Sources'', p. 429; Woolf, ''Pictland to Alba'', 168–173; Smyth, ''Warlords and Holy Men'', pp. 203–204; Stenton, ''Anglo-Saxon England'', pp. 342–343; Scragg, "''Battle of Brunanburh''".</ref>

[[Brunanburh]], for all that it had been a famous and bloody battle, settled nothing. On 27 October 939 Æthelstan, the "pillar of the dignity of the western world" in the words of the ''Annals of Ulster'', died at [[Malmesbury]]. He was succeeded by his brother [[Edmund I|Edmund]], then aged 18. Æthelstan's realm, seemingly made safe by the victory of Brunanburh, collapsed in little more than a year from his death when Amlaíb returned from Ireland and seized Northumbria and the Mercian Danelaw. Edmund spent the remainder of Constantín's reign rebuilding his kingdom.<ref>Woolf, ''Pictland to Alba'', p. 174; Stenton, ''Anglo-Saxon England'', pp. 356–359; Higham, ''Kingdom of Northumbria'', p. 193; Blair, ''Anglo-Saxon England'', pp. 87–89.</ref>

For Constantine's last years as king, there is only the meagre record of the ''Chronicle of the Kings of Alba''. The death of Æthelstan is reported, as are two others. The first of these, in 938, is that of [[Dubacan of Angus|Dubacan]], [[mormaer of Angus]] or son of the mormaer. Unlike the report of 918, on this occasion, the title mormaer is attached to a geographical area, but it is unknown whether the Angus of 938 was in any way similar to the later mormaerdom or earldom.<ref>Woolf, ''Pictland to Alba'', pp. 175, 211–212.</ref> The second death entered with that of Æthelstan, is that of Eochaid mac Ailpín, who might, from his name, have been a kinsman of Constantín.<ref>Woolf, ''Pictland to Alba'', p. 175.</ref>

== Abdication and posterity ==
By the early 940s, Constantine was an old man in his late sixties or seventies. The [[kingdom of Alba]] was too new to be said to have a customary rule of succession, but Pictish and Irish precedents favoured an adult successor descended from [[Kenneth MacAlpin]]. Constantine's surviving son [[Indulf]], probably baptised in 927, would have been too young to be a serious candidate for the kingship in the early 940s, and the obvious heir was Constantine's nephew, [[Malcolm I]]. As Malcolm was born no later than 901, by the 940s he was no longer a young man and may have been impatient. Willingly or not — the 11th century ''[[The Prophecy of Berchán]]'', a verse history in the form of a supposed prophecy, states that it was not a voluntary decision — Constantine abdicated in 943 and entered a monastery, leaving the kingdom to Malcolm.<ref>Woolf, ''Pictland to Alba'', p. 175; Anderson, ''Early Sources'', pp. 444–448; Broun, "Constantine II".</ref>

Although his retirement might have been involuntary, the ''Life'' of [[Cathróe of Metz]] and ''The Prophecy of Berchán'' portray Constantine as a devout king. The monastery to which Constantine retired, and where he is said to have been [[abbot]], was probably that of [[Church of St Mary on the Rock|St Andrews]]. This had been refounded in his reign and given to the reforming [[Céli Dé]] (Culdee) movement. The Céli Dé were subsequently to be entrusted with many monasteries throughout the kingdom of Alba until replaced in the 12th century by new orders imported from [[France]].<ref>Anderson, ''Early Sources'', pp. 431–444; Broun, "Constantine II"; Woolf, ''Pictland to Alba'', p. 175; MacQuarrie, ''Saints of Scotland'', pp. 199–210. ''The Prophecy of Berchán'' describes Constantine's "fair, long reign" as a time "with fruit upon slender branches, with ale, with music, with good cheer; with corn, with milk, with nimble cattle; with pride, with fortune, with [worth]"; Anderson, ''Early Sources'', pp. 447–448.</ref>

Seven years later the ''Chronicle of the Kings of Alba'' says:
{{blockquote|[Malcolm I] plundered the English as far as the [[river Tees]], and he seized a multitude of people and many herds of cattle: and the Scots called this the raid of Albidosorum, that is, Nainndisi. But others say that Constantine made this raid, asking of the king, Malcolm I, that the kingship should be given to him for a week's time so that he could visit the English. In fact, it was Malcolm I who made the raid, but Constantine incited him, as I have said.<ref>Anderson, ''Early Sources'', pp. 452–453.</ref>}} Woolf suggests that the association of Constantine with the raid is a late addition, one derived from a now-lost saga or poem.<ref>Woolf, ''Pictland to Alba'', pp. 178–181.</ref>

Constantine's death in 952 is recorded by the Irish annals, who enter it among ecclesiastics. His son Indulf would become king on Malcolm's death. The last of Constantine's certain descendants to be king in Alba was a great-grandson, [[Constantine III of Scotland|Constantine III]] (Constantín mac Cuiléin). Another son had died at Brunanburh and according to John of Worcester, [[Amlaíb mac Gofraid]] was married to a daughter of Constantine. It is possible that Constantine had other children, but like the name of his wife, or wives, this has not been recorded.<ref>Woolf, ''Pictland to Alba'', pp. 171, 175, 177; Duncan, ''Kingship of the Scots'', p. 345, table A; Anderson, ''Early Sources'', p. 451.</ref>

The form of kingdom which appeared in Constantine's reign continued in much the same way until the [[Davidian Revolution]] in the 12th century. As with his ecclesiastical reforms, his political legacy was the creation of a new form of Scottish kingship that lasted for two centuries after his death.<ref>Broun, "Constantine II". The nature of that kingdom is, however, still a matter of debate, see Woolf, ''Pictland to Alba'', pp. 342–350; {{citation |last=Grant |first=Alexander |contribution=The Construction of the Early Scottish State |title=The Medieval State: Essays presented to James Campbell |editor-last=Maddicott |editor-first=J. R. |editor2-last=Palliser |editor2-first=D. M. |publisher=Hambeldon |year=2000 |location=London |isbn=1-85285-195-3}}.</ref>

== Family ==
The name of Constantine's wife is not known, however, they are known to have had at least 3 children:
* Ildulb mac Causantín (Indulf or Indulph)(died 962), king of Alba 954–962;
* Cellach, died in 937 in the [[Battle of Brunanburh]];
* A daughter, name not recorded, married [[Amlaíb mac Gofraid]].

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* {{citation |last=Swanton |first=Michael |title=The Anglo-Saxon Chronicle |year=1996 |publisher=Routledge |location=New York |isbn=0-415-92129-5}}
* {{citation |editor-last=Taylor |editor-first=Simon |title=Kings, clerics and chronicles in Scotland 500–1297 |year=2000 |publisher=Four Courts Press |location=Dublin |isbn=1-85182-516-9}}
* {{citation |last=Woolf |first=Alex |author-link=Alex Woolf |title=From Pictland to Alba, 789–1070 |year=2007 |series=The New Edinburgh History of Scotland |publisher=Edinburgh University Press |location=Edinburgh |isbn=978-0-7486-1234-5}}
{{refend}}

== External links ==
* {{PASE|67962|Constantine 2}}
* [https://www.royal.uk/constantine-ii-r-900-943 Constantine II] at the official website of the [[British monarchy]]

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{{English, Scottish and British monarchs}}
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[[Category:9th-century Scottish monarchs]]
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[[Category:10th-century Christian monks]]
[[Category:10th-century Scottish monarchs]]
[[Category:Monarchs who abdicated]]
[[Category:Burials in Iona]]