This famous surname is one of the most ancient names of Ireland. Numerically, with some twenty thousand nameholders, it is also one of the most popular, being twelfth in the table of numerical strength of Irish surnames. Originally the Clan Doyle, derived from the pre 10th century Gaelic 'Dhubh-ghall' (The dark stranger) was found mostly in the counties of South-East Leinster, (Wicklow, Wexford and Carlow) and surprisingly it largely remains so today, the name being rare in other regions. There is a traditional belief that the ancestor who gave his name to the family was a descendant of one of the Norsemen who settled in Ireland in pre-Norman times, and this is probably partly true. However if the original nameholders were dark, this suggests that a more likely explanation is that they were either 'Celts' (Olde English fleeing the Anglo-Saxon invaders of Northern England), or possibly Danes, who were much darker than the Norsemen, and who had established themselves in Ulster, the West of Scotland, and the Isle of Man. The surname is not included in the 'Gaelic Genealogies' which supports the view of 'Viking' entry. Be that as it may, the 'Doyle's', the clan is never known as O' Doyle, have made their mark on Irish history, and particularly in the Catholic Church. The Scottish form of Doyle is (Mac) Dougall, and this name was also used in the same way as a byname distinguishing darker-haired Danes from fair-haired Norwegians. The best-known bearer of the name is probably Sir Arthur Conan Doyle, (1859 - 1930), the creator of Sherlock Holmes, whilst an outstanding churchman was J K L Doyle, Bishop of Kildare (1786 - 1834). The first recorded spelling of the family name is shown to be that of O'Dubhghaill, which was dated 978, in the "Annals of the Four Masters", during the reign of Brian Boru, High King of Ireland, 940 - 1014. 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.