Editing Letterkenny (section)

==Toponymy==
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| caption2  = Above: The Market Square district {{c.}} 1900; <br />
Below: The Market Square district {{c.}} 2007
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Letterkenny takes its name from the Irish ''Leitirceanainn'', meaning "Hillside of the O'Cannons" – the O'Cannons being the last of the ancient chieftains of [[Tír Conaill]]. While no evidence of forts or castles belonging to the O'Cannon clan exists in the Letterkenny district, eight miles west of Letterkenny is located Doon Rock, believed by some to be an ancient inauguration site of the O'Cannon Kings.

The O'Cannon dynasty is descended from [[Conn of the Hundred Battles]] and [[Niall of the Nine Hostages]], two of Ireland's [[High King of Ireland|ancient High Kings]]. The O'Cannons have been described as 'Ancient Princes of Tír Connaill' and 'Valiant Chiefs'. Their 350-year dynasty in Tír Connaill ended in 1250. Their ancient territory is recorded as being in Tír Aeda (now the [[Baronies of Ireland|barony]] of [[Tirhugh]]) in what is now South Donegal. After the deaths of Ruairí Ó Canannain (Rory O'Cannon) and his son Niall Ó Canannain in 1250, the [[sept]] declined greatly in power. Brian Ó Néill (Brian O'Neill) died ten years later in 1260; he had supported an Ó Canannain claimant to Tír Conaill, i.e. to the Kingdom of Tír Conaill (Tirconnell). However, the O'Cannon Clan remained subservient to the [[O'Donnell Clan]], the Kings of Tír Chonaill from the early thirteenth century onwards after Gofraid O'Donnell helped the English defeat the O'Cannons in 1250. The personal name Canannain is a diminutive of Cano meaning 'wolf cub'. Canannain was fifth in descent from [[Flaithbertach mac Loingsig]] (died [[765 in Ireland|765]]), [[high-king]] of Ireland; they were the descendants of [[Niall of the Nine Hostages]] (Irish: Niall Noigiallach), who died {{c.}} [[405 in Ireland|405]] A.D., by his son [[Conall Gulban]], who gave his name to [[Tír Conaill]], the 'Land of Conall', now County Donegal.

By the early 17th century, the name Uí Canannain had been [[anglicised]] to O'Cannon. Further anglicisation took place during the [[Penal Laws (Ireland)|Penal Laws]] in the late 18th and early 19th centuries and the name in Co. Dun na nGall became Cannon. In the early 1880s, there were just 200 families bearing the Cannon surname living in County Donegal, who were mainly tenant farmers. The Cannons/O'Canannains were of the ancient sept of Cenell Conaill, a branch of the northern Uí Néill and descend from Ruaidrí ua Canannain (died 30 November 950), King of Cenel Conaill, and grandson of Canannain, who flourished in the second half of the 9th century. The site of the ancient seat of the Ó Canannain was near Letterkenny (the largest town of County Donegal only since the 1950s), which is said to represent the countryside of the O'Cannons (English translation).