Perhaps not surprisingly this famous Irish surname is recorded in many spellings. Deriving from the ancient Gaelic pre 10th century 'Mac giolla Chuda', which translates as 'the son of the follower of St Mochda', these spellings include MacGillacuddy, MacGillicuddy, McGillicuddy, McGillycuddy, MacCuddy, Gillicuddy, Gillycuddy, Cody, Cuddy, and even Archdeacon! The surname originates from County Kerry and is much associated with MacGillycuddy's Reeks, the highest mountain chain in Ireland, and named after the clan. This in itself is very unusual. Most locational surnames are the other way around, the placename preceeding the surname, often by many centuries. In addition the clan is one of the few Irish clans which follow or at least have retained the title for the chief of 'MacGillycuddy of the Reeks'. In Scotland it would have been 'of that Ilk' but the concept is the same. It seems however that the clan only adopted its name in the 16th century, which begs the question as to what the mountains were called before that date? It seems that previous to about 1550 they were a branch of the O'Sullivan Mor clan. By the end of that century the MacGillyuddys were the principle landowners in the baronies of Dunkerron and Magunity. Amongst the earliest known nameholders was Colonel Denis MacGillycuddy, who it is said, commanded an Irish Brigade in the French Army of 1680.