Anglicized form of Gaelic McRobhartaigh, patronymic from the personal name Robhartach,
meaning The Great Hand of the House or Kingdom.

Columba or Columcille was born on December 7 521 AD in Gartan, now County Donegal, part of the Province of Ulster in the north of Ireland. He was born to royalty, into the Clan Ó Domhnaill (O’Donnell Clan). His father, Feidlimid was the great-great-grandson of Niall of the Nine Hostages, an Ard Ri or Irish high king of the 5th
century. His mother, Eithne, was of the royal house in Leinster, of the Catlmoir Mor.

Columba was a visionary credited not only with helping to bring Christianity to Ireland, but also with imparting the first Irish surnames to his kin, the Robhartaighs, or McGroartys, to establish genealogical rights.
In Derry and Donegal, Columba's family held lands which were part of his monastic settlements; in both places they were known as Ballymagroarty, which translates litterally to The McGroarty Homeland. In the middle ages, each parish had a herenach family whose duty it was to take charge of and preserve the church relics. The family would have at least one monk or holy man.
In Derry and Donegal, the McGroarty’s were the herenachs. It was here at Ballymagroarty the McGroartys kept Ireland's second-most famous text (after the Book of Kells) the Cathach of St. Columba for centuries after St. Columba's death in 597 AD.

The Cathach at the Royal Irish Academy, written by St. Columba between 560 - 597 AD and one of Ireland's oldest treasures, exist to this day because of his descendants - the McGroartys of Donegal.

Cenél Conaill is the name of the "kindred" or descendants of Conall Gulban, son of Niall Noígiallach defined by oral and recorded history and of the O'Donnell dynasty. They were also known in Scotland as the Kindred of Saint Columba.