Recorded in several forms including Mulleary, Mulry, Mulroy, Milroy and Roy, this is clearly a Gaelic surname, although its origins are open to a number of possible interpretations. These include derivation from the ancient Scottish name Mac Illeruaidh or Mac gille Ruaidh meaning 'The son of the red haired lad', although MacLysaght, the famous Irish historian claims it is from O' Maolmhuire, meaning a follower of the Virgin Mary! A completely different explanation is that it may be ethnic, and to have referred to an Anglo-Saxon as they often had red hair. It is said that the the surname was first recorded in Scotland in the medieval period with early recordings including Donald M'Gilleroi, a notary public in 1465, and Ade M' Gilroy, a tenant of Eglisdisdane and Balnegreagane in the Exchequer Rolls of Scotland, in 1480. Milroy, from M' Ilroy with omission of the apostrophe, is widespread in Ayrshire and Wigtownshire, whilst in Ireland as Mullery and Mulleary, it is associated with County Roscommon. Interesting recordings include John Milroy of Fintallock, a covenanter, who was hanged at Wigtown in 1685, whilst others of the name were obliged to flee from religious persecution. The surname is also found in the abbreviated form Roy. The earliest known recording is proably that of Michael M'Gilrey, a tenant of Thornhill, Dumfriesshire, which was dated 1376. This is in the Ancient charters of the earldom of Morton, during the reign of King Robert 11 of Scotland, 1371 - 1390. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.