This interesting surname is of Irish origin, and is an Anglicization of the Old Gaelic name "O'Ceanndhubhain", the Gaelic prefix "O" meaning grandson or male descendant (of), and the personal name, "Dubhain", meaning "little black-headed one", from the Gaelic elements "ceann", head; "dubh", black; and the diminutive suffix "-an". Traditionally, Irish family names are taken from the heads of tribes, or from some illustrious warrior, and are usually prefixed by "O", as above, or "Mac", denoting "son of". The O'Canavans were hereditary physicians to the O'Flahertys of Lemonfield (County Galway); it was (and is) primarily a County Galway name. Today the surname is almost always written without the prefix "O", and though distributed throughout the four provinces is still most widespread in the Connacht Counties of Galway and Mayo. Canavan has been Anglicized as Guinevan in County Waterford, and as Whitehead in County Armagh. The marriage of James Canavan and Catherine Dunne was recorded at Ballina, County Kildare, on November 3rd 1810. The first recorded spelling of the family name is shown to be that of O Ceanndhubhain of Connemara, which was dated 1416, in the "Annals of the Four Masters", Ireland, during the reign of King Henry V of England, known as "The Victor of Agincourt", 1413 - Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.1422.