This interesting surname, found in Ireland and Scotland, is of Old Gaelic origin, and is the Anglicized form of the Gaelic "Mac GiollaEaspuig", composed of the Gaelic prefix "Mac", meaning son of, "giolla", servant of, and "easpuig", bishop; hence "son of the bishop's servant". The surname may be found with the prefix "Mac", though this is rare. In Ireland the name is chiefly found in County Down, and is first recorded in the Gaelic form here towards the end of the 12th Century (see below). In Scotland, one Ewan filius Gillaspeck witnessed a charter by Alwin, earl of Levenax, circa 1199. The County Down family later appear as erenaghs of Kilraine (Killybegs, County Donegal). The leader of the Scots who slew Shane O'Neill in 1567 was William Gillespie. Irish records indicate that the name was chiefly found in north Ulster in the 16th and 17th Centuries, and is still numerous there. Sir Robert Rollo Gillespie (1766 - 1814), born in County Down, had an adventurous and distinguished career as a soldier in India, where he was killed in action. A Coat of Arms granted to a Scottish family depicts a silver chevron wavy between three red roses, gold slipped on a silver shield. The first recorded spelling of the family name is shown to be that of Mac GiollaEpscoip (no known personal name), who was chief of Aeilabhra (barony of Iveagh, County Down), which was dated circa 1175, in the "Medieval Irish Records", during the reign of Rory O'Conor, known as "The High King of Ireland", 1166 - 1175. 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.