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. (April 2019)
The Kingdom of Gwynedd (Medieval Latin: Venedotia or Norwallia; Middle Welsh: Guynet) was 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, the rulers of Gwynedd repeatedly rose to dominance and were acclaimed as "King of the Britons" before losing their power in civil wars or invasions. The kingdom of Gruffydd ap Llywelyn—the King of Wales from 1055 to 1063—was shattered by a Saxon invasion in 1063 just prior to the Norman invasion of Wales, but the House of Aberffraw restored by Gruffudd ap Cynan slowly recovered and Llywelyn the Great of Gwynedd was able to proclaim the Principality of Wales at the Aberdyfi gathering of Welsh princes in 1216. In 1277, the Treaty of Aberconwy granted peace between the two but would also guarantee that Welsh self-rule would end upon Llewelyn's death, and so it represented the completion of the first stage of the conquest of Wales by Edward I.
Welsh tradition credited the founding of Gwynedd to the Brittonic polity of Gododdin (Old Welsh Guotodin, earlier Brittonic form Votadini) from Lothian invading the lands of the Brittonic polities of the Deceangli, Ordovices, and Gangani in the 5th century. The sons of their leader, Cunedda, were said to have possessed the land between the rivers Dee and Teifi. The true borders of the realm varied over time, but Gwynedd Proper was generally thought to comprise the cantrefs of Aberffraw, Cemais, and Cantref Rhosyr on Anglesey and Arllechwedd, Arfon, Dunoding, Dyffryn Clwyd, Llŷn, Rhos, Rhufoniog, and Tegeingl at the mountainous mainland region of Snowdonia opposite.
The name Gwynedd is believed to be an early borrowing from Irish (reflective of Irish settlement in the area in antiquity), either cognate with the Old Irish ethnic name Féni, "Irish People", from Primitive Irish *weidh-n- "Forest People"/"Wild People" (from Proto-Indo-European *weydh- "wood, wilderness"), or (alternately) Old Irish fían "war band", from Proto-Irish *wēnā (from Proto-Indo-European *weyH1- "chase, pursue, suppress").
The 5th-century Cantiorix Inscription now in Penmachno church seems to be the earliest record of the name. It is in memory of a man named Cantiorix, and the Latin inscription is Cantiorix hic iacit/Venedotis cives fuit/consobrinos Magli magistrati: "Cantiorix lies here. He was a citizen of Gwynedd and a cousin of Maglos the magistrate". The use of terms such as "citizen" and "magistrate" may be cited as evidence that Romano-British culture and institutions continued in Gwynedd long after the legions had withdrawn.