Recorded in a wide variety of spellings including MacNeilage, MacNeiledge, MacNelis, MacNellus, and the short forms commencing M' or Mc, this is an ancient Scottish surname of Gaelic pre 10th century origins. It derives from MacNiallghus meaning the 'son of the champion'. The clan or sept being originally associated with the county of Dumbartonshire, but now found both in Scotland and Northern Ireland. Most early Scottish and Irish surnames originate from a 'nickname' given to the first naheholder or clan chief, and this is no exceptiont. Early examples of the surname recordings taken from authentic rolls, charters and registers dating back to the 15th century include: Cristin M'Nelos who witnessed a land charter by the Clan Lamont in 1465, whilst Alexander McNellus was an civil official engaged by Sir George Calbrathe in 1496 to collect rents and other debts. In the year 1500 Gillaspy McNelus was a murder victim, Archibald McNelus was a miller in Campsaill in 1598, and finally Gilbert M'Neilladge was a burgess and charter witness at Rothesay in 1663.