Editing T and O map (section)

{{short description|Type of medieval world map}}
[[File:T and O map Guntherus Ziner 1472.jpg|thumb|This T and O map, from the first printed version of [[Isidore of Seville|Isidore]]'s ''[[Etymologiae]]'', identifies the three known continents as populated by descendants of Sem ([[Shem]]), Iafeth ([[Japheth]]) and Cham ([[Ham, son of Noah|Ham]]).]]
[[File:Hereford Mappa Mundi 1300.jpg|thumb|right|200px|''The [[Hereford Mappa Mundi]]'', ca. AD 1300, [[Hereford Cathedral]], England.  A classic "T-O" map with Jerusalem at center, east toward the top, [[Europe]] at bottom left and Africa on the right.]]

A '''T and O map''' or '''O–T''' or '''T–O map''' (''orbis terrarum'', orb or circle of the lands; with the letter T inside an O), also known as an '''Isidoran map''', is a type of [[Early world maps|early world map]] that represents the [[Afro-Eurasia|Afro-Eurasian landmass]] as a circle (= O) divided into three parts by a T-shaped combination of the Mediterranean sea, the river Tanais (Don) and the Nile.<ref>David Woodward, "Medieval ''Mappaemundi''", in ''The History of Cartography'', Vol. 1: ''Cartography in Prehistoric, Ancient, and Medieval Europe and the Mediterranean'', ed. J. B. Harley and David Woodward (Chicago: University of Chicago Press, 1987), 296.</ref> The origins of this diagram are contested, with some scholars hypothesizing an origin in Roman or late antiquity, while others consider it to have originated in 7th or early-8th century Spain.<ref>For an overview of the different scholarly positions on the origins of the diagrammatic form, see Christoph Mauntel, "The T-O Diagram and its Religious Connotations – a Circumstantial Case", in ''Geography and Religious Knowledge in the Medieval World'', ed. Christoph Mauntel (Berlin: de Gruyter, 2021), 60-65.</ref>

The earliest surviving example of a T-O map is found in a late-7th or early-8th century copy of [[Isidore of Seville|Isidore of Seville's]] (c. 560–636) ''De natura rerum'', which alongside his ''[[Etymologiae]]'' (c. 625) are two of the most common texts to be accompanied by such a diagram in the Middle Ages.<ref>El Escorial, Real Biblioteca, R.II.18, fol. 24v; see also Mauntel, "The T-O Diagram and its Religious Connotations", 61 and Woodward, "Medieval ''Mappaemundi''", 301.</ref> A later manuscript added the names of [[Generations of Noah|Noah's sons]] ([[Shem|Sem]], [[Japheth|Iafeth]] and [[Ham, son of Noah|Cham]]) for each of the three continents (see [[Biblical terminology for race]]).<ref name=Williams13>{{harvnb|Williams|1997|p=13}}: "...the Isidoran tradition, as it was known from peninsular examples, including the earliest of the ubiquitous T-O maps. This emblematic figure appears twice at the foot of folio 24v in a copy of Isidore's De Natura Rerum, now Escorial R.II.18. [...] When, in the ninth century, the Escorial manuscript fell into the hands of Eulogius and was supplemented, this precise text (Etymologiae XIV, 2, 3) was placed on the page, folio 25r, facing the primitive map and was introduced another small T-O map. To this later T-O diagram, however, were added the names of Noah's sons- Shem, Japheth and Ham, for Asia, Europe and Africa, respectively-outside the circle of the globe. This apportionment is only implicit in the Bible (Genesis 9: 18-19). Josephus (d. c.100 AD) is more explicit as was Hippolytus of Rome, whose chronicle of 234 in its Latin translation disseminated the Noachid distribution in the West. Isidore's Etymologiae, however, the distribution of Noah's sons is not highlighted, but only incidentally reported with the description of the location of cities in Book IX. It seems clear, if we accept the evidence of Escorial R.II.18, that the Shem-Japheth-Ham distribution was not in the primitive Isidoran diagram. This means that Isidore's use of the T-O diagram was not informed by any overt religious content."</ref> A later variation with more detail is the [[Beatus map]] drawn by [[Beatus of Liébana]], an 8th-century Spanish [[monk]], in the prologue to his ''[[Commentary on the Apocalypse]]''.