TYWYSOG

'Tywysog' is Welsh for a ruling Prince or King. The feminine form is Tywysoges. The work Brut y Tywysogion is the Annals of the Princes of Wales and is a historical narrative of the deeds of the various rulers of the petty kingdoms which existed in Wales from the end of Roman rule in Britain in c.410AD to the final conquest of Wales and the death of its last consecrated native ''Tywysog'' Llywelyn ap Gruffydd of the Kingdom of Gwynedd in 1282. Another Tywysog was proclaimed in Owain Glyndŵr, Lord of Glyndyfrdwy, and heir to the Kingdom of Powys in 1400 but this too was extinguished by 1412.
It is cognate with ''taoiseach'' in Irish Gaelic and ''tòiseach'' in Scottish Gaelic; the latter forms an element in "MacIntosh" (Mac an Tòisich). Both words originally had a similar meaning in the Goidelic languages to ''tywysog'', with ''taoiseach'' coming to mean the Irish head of government, and ''tòiseach'' a Scottish clan chief.