Cemais was one of the three medieval cantrefs on the island of

Anglesey Anglesey (; cy, (Ynys) Môn ) is an island off the north-west coast of Wales. It forms a principal area known as the Isle of Anglesey, that includes Holy Island across the narrow Cymyran Strait and some islets and skerries. Anglesey island ...

, north

Wales Wales ( cy, Cymru ) is a country that is part of the United Kingdom. It is bordered by England to the east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in ...

, in the

Kingdom of Gwynedd The Kingdom of Gwynedd (Medieval Latin: ; Middle Welsh: ) was a Welsh kingdom and a Roman Empire successor state that emerged in sub-Roman Britain in the 5th century during the Anglo-Saxon settlement of Britain. Based in northwest Wales, th ...

. It lay on the northern side of the island on the

Irish Sea The Irish Sea or , gv, Y Keayn Yernagh, sco, Erse Sie, gd, Muir Èireann , Ulster-Scots: ''Airish Sea'', cy, Môr Iwerddon . is an extensive body of water that separates the islands of Ireland and Great Britain. It is linked to the Ce ...

. The cantref consisted of the two

cwmwd A commote ( Welsh ''cwmwd'', sometimes spelt in older documents as ''cymwd'', plural ''cymydau'', less frequently ''cymydoedd'')'' Geiriadur Prifysgol Cymru'' (University of Wales Dictionary), p. 643 was a secular division of land in Medieval Wal ...

s of Talybolion and Twrcelyn.

See also