The name Ferguson (or Fergusson) and its history spreads from Argyle and Kintyre on the west coast of Scotland (then known as Dál
Riata), but also as far across as Antrim in northeastern Ireland under
Fergus Mór mac Eirc. Evidence suggests that the clan also spread right across the Scottish Highlands as far as Dunkeld. Through emigration, either forced or voluntary, the name Ferguson and its rich heritage have travelled throughout the world.
The origin of the name Fergusson or Ferguson, "son of Fergus" (MacFhearguis in Gaelic), is shrouded by the mists of time. Medieval historians recorded a tradition that the founder of Scotland's monarchy was a Fergus who lived in Ireland about 300 B.C. Traditions tell that by 500 A.D. the Scots under Fergus Mór mac Eirc had left Northern Ireland and became established in Dál Riata, now
Argyll. From Fergus Mor, with a few early exceptions, descend all subsequent kings and queens of the Scots, including the present Queen of Britain. St.
Columba of Iona (6th century A.D.) was a scion of Fergus
Mor's royal line.
According to Medieval historians Fergus was the founder of the Scottish monarchy. Ayrshire and
Dumfries Fergussons alike claim descent from Fergus of Galloway. The grandfather of
Donnchadh, Earl of Carrick and in turn
great-great-grandfather to Robert Bruce, Fergus, restored the see of Whithorn and founded Dundrennan Abbey during the reign of David I and Malcolm IV. He died as a monk at Holyrood in
1161. Through Robert Bruce passes the line of the Royal Family of Britain. It was the 1st Earl of
Carrick's signature that might suggest the origins of the Fergusson surname, Duncan, son of Gilbert, the son of Fergus, hence MacFhearguis.