This name with variant spelling (Mac)Crossan, is an Anglicized form of the Gaelic Irish "Mac an Chrosain", a patronymic, "Mac", "son of" plus "crosan", reciter of satirical verse, hence, "son of a satirist". Originally the surname may have denoted one who carried a cross in religious processions of the Christian Church. There are two distinct septs of the MacCrossans, the most numerous is of North Ulster, now mainly in County Tyrone and County Derry. In Tyrone the prefix "mac" has been retained, but in County Derry it has been dropped. Richard MacCrossan from this sept was Bishop of Raphoe in the 14th Century. The other sept were from Mid Leinster, and Ballymacrossan, County Laois is named after this sept. These MacCrossans however, have long disguised their name under the English form of Crosby or Crosbie. The Chancery Rolls of 1550 record the pardon of one Owen Oge MacCrossan of Ballymacroosan, County Laois. The first recorded spelling of the family name is shown to be that of Henry MacCrossan, which was dated circa 1350, Bishop of Raphoe, during the reign of King Edward 111, known as "The Father of the Navy", 1327 - 1377. 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.