Riley History, Family Crest & Coats of Arms

The Riley surname originally appeared in Gaelic as Ó Raghailligh, which means descendant of Raghallach.

Early Origins of the Riley family

The surname Riley was first found in County Cavan. They were known as the Princes of East Breffny, descended from Raghallaigh, Prince of Breffny in 981. They maintained their territory during the Anglo/Norman invasion of Strongbow, Earl of Pembroke, in 1172, but Sir John O’Reilly, Prince of Breffny surrendered the principality to Queen Elizabeth I thereby ensuring that his territories remained intact.