This is an anglicized form of the Olde Scottish Gaelic MacCarsane. The Gaelic prefix "mac" means "son of", plus the personal name Carsane which in turn is locational from a now lost place in Galloway called Carsan; hence, "son of one who came from Carson". The placename itself was believed to derive from the Welsh "cors" meaning "bog" or "fen", and the surname from this source was first recorded towards the end of the 13th Century, (see below). The patronymic form first appears in the 15th Century - Thomas Makcarsane of Kirkcudbright - "Accounts of the Lord High Treasurer", Scotland. One, Andrew M' Carsane, witness in Wigtownshire, was recorded in the "Register of the Great Seal of Scotland" in 1546. The form MacCarrison is now most widespread in Ulster. On September 22nd 1831, the birth of one, Mary McCarrison was recorded in Dromore Parish, County Down. The first recorded spelling of the family name is shown to be that of Sir Robert de Carsan, which was dated 1276 - "Records of Holm Cultram", during the reign of King Alexander III of Scotland, 1249 - 1286. 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.