Reilly
also O'Reilly, Riley, Ó Raghallaigh
Kings of East Bréifne — and the family that gave English the phrase 'the Reilly money'.
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The seat of Reilly
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Stake your name →What does the Reilly name mean?
From Ó Raghallaigh — descendant of Raghallach. Raghallach was an early-tenth-century chief of East Bréifne, killed at the battle of Clontarf in 1014 fighting alongside Brian Boru. His descendants took the surname in the eleventh century and ruled the kingdom of East Bréifne — modern county Cavan with parts of Longford, Meath and Westmeath — until the early seventeenth century. The English form Reilly (with or without the apostrophe-O) is dominant today; Riley is a parallel American spelling of the same name.
The history of Reilly
The Ó Raghallaigh kings of East Bréifne ran their kingdom as a near-independent palatinate of the late mediaeval Irish world from the 11th century to the early 17th. Their seat was at Tullymongan above modern Cavan town, and they minted their own coinage in the 1480s — the 'O'Reilly's money', a small silver coin produced at Cavan and accepted in trade across the north midlands. The English idiom 'the life of Reilly' for a comfortable existence is sometimes traced to this tradition of the family's relative prosperity, though the etymology is contested.
Hugh O'Reilly, Catholic Archbishop of Armagh from 1628 to his death in 1653, was the central churchman of the Confederation of Kilkenny — the de-facto Catholic government of Ireland through the 1640s. The line lost its political ground in the Cromwellian confiscation of 1652 and again in the Williamite confiscation of 1691. The surname survived: Cavan today is still by far the densest O'Reilly county on the island, and the diaspora-Reillys of America (typically dropping the apostrophe-O) include the writer Bill O'Reilly, the actor John C. Reilly, and an outsized share of the New York and Boston Catholic Irish families.
Notable bearers of the Reilly name
- Hugh O'Reilly (c.1581–1653) — Archbishop of Armagh, Confederation of Kilkenny
- Edmund O'Reilly (1606–1669) — Archbishop of Armagh, Restoration-era
- John C. Reilly (b. 1965) — actor
- James Whitcomb Riley (1849–1916) — American poet, Indiana-Riley line
Frequently asked
What does the surname Reilly mean?
Where does the Reilly family come from?
Who are some famous Reillys?
Is O'Reilly the same family as Reilly?
Editor notes
- · Verify the etymology of 'the life of Riley' — the popular Reilly attribution is plausible but not the only candidate.