Clan Rising

Reilly

also O'Reilly, Riley, Ó Raghallaigh

Kings of East Bréifne, and the family that gave English the phrase 'the Reilly money'.

Origin
Ulster, Ireland
Motto
Fortitudine et prudentia
Famous bearer
Hugh O'Reilly (c.1581–1653), Archbishop of Armagh, Confederation of Kilkenny
Register
Irish family
Territory of Reilly

CoreHistoric reach

The seat of Reilly

Seat vacant

Chief

No one leads the Reilly community yet. When the movement opens, you can stand for its leadership, or help elect whoever does.

Current mission

No shared goal set yet. Once Reilly has leadership, it sets the public focus: a restoration, a gathering, a real-world project that helps its own.

The Reilly clan is being rebuilt. Join the waiting list for the movement today, and you help decide who leads it and what it does.

Help rebuild the Reilly clan →

Motto

Fortitudine et prudentia

“By fortitude and prudence”

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 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.

Champions of the Reilly name

The bearers whose lives are inseparable from this surname. Each has their own page, biography, achievements, geography, connection to the family.

Castles the Reilly held

Strongholds this name held for a decade or more, look one up, or rebuild it to explore.

  • Cloughoughter Castle

    The O'Reilly clan took possession in 1233, completed the castle and retained it for centuries; Philip O'Reilly held it again, 1641–53.

  • Ballinlough Castle

    Home of the O'Reillys from the seventeenth century; Sir Hugh O'Reilly added a new wing around 1790.

  • Castle Saunderson

    The O'Reillys of Breffni held the original castle, known as Breffni Castle, from the 14th century until the Plantation of Ulster.

The castles of the homeland

The great strongholds of the homeland, look one up, see what it looked like in its prime, and recreate it to explore.

Ashford Castle, County Mayo, IrelandAshford Castle, County MayoRestored · prime 1880Manderley Castle, IrelandManderley CastleRestored · prime 1840Dublin Castle, IrelandDublin CastleRestored · prime 1790

All castles in Ireland → · Strongest castles in Ireland → · Castles of Europe

Play As Your Clan

Explore history as a ReillyStart your story →

Pick any year from 500 to 1945 and any place on earth, the Reilly country, or a shore no Reilly ever reached. The chronicler sets the scene; the deeds are yours.

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?

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 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.

Where does the Reilly family come from?

The Reilly family is rooted in Ulster, in Ireland. Within that, the name was particularly concentrated in Cavan. The atlas page for the name records the historical territory it has held over the centuries.

Where did the Reilly family historically hold territory?

At its greatest historical extent, the Reilly name has been concentrated in Longford, Meath, Westmeath and Monaghan. The atlas page distinguishes the core territory of the name from this wider historical reach with hatched silhouettes on the map.

Is Reilly Irish or Scottish?

Reilly is a Irish surname; its home on this atlas is Ireland, where the historical territory and family record of the name are concentrated. The same or similar spellings can surface in Scottish records, but the lineage documented on this page is the Irish one.

How old is the Reilly surname?

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. European hereditary surnames crystallised broadly between the 12th and 14th centuries, and the Reilly name took its modern form within that long settlement.

What is the Reilly family known for?

Kings of East Bréifne, and the family that gave English the phrase 'the Reilly money'. 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.

What is the Reilly motto?

The motto of the Reilly family is "Fortitudine et prudentia", which translates as "By fortitude and prudence". Family mottoes were registered with the chief of the name and carried on the heraldic arms and battle-banners.

What does "Fortitudine et prudentia" mean in English?

"Fortitudine et prudentia" is the motto of the Reilly family. In English it means "By fortitude and prudence". The phrase is typically rendered in Latin, though some Highland families carry their motto in Gaelic and some Norman lines in Old French.

Is there a Reilly family crest or coat of arms?

There is no single coat of arms that belongs to everyone named Reilly. Heraldic arms were granted to individuals and descend through specific documented lines, so a "family crest" matched to a surname alone is decorative rather than genealogical. The motto associated with the principal line is "Fortitudine et prudentia".

Who is the most famous Reilly?

The best-known bearer of the Reilly name is Hugh O'Reilly (c.1581–1653), Archbishop of Armagh, Confederation of Kilkenny. Other prominent figures of the family include Edmund O'Reilly (1606–1669), Archbishop of Armagh, Restoration-era, John C. Reilly (b. 1965), actor and James Whitcomb Riley (1849–1916), American poet, Indiana-Riley line.

Who are some famous Reillys?

Notable bearers of the Reilly name include 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 and James Whitcomb Riley (1849–1916), American poet, Indiana-Riley line. Each is profiled on the family page, with cross-links to the geography, stories, and historical events tied to their life.

Is O'Reilly the same family as Reilly?

Yes. O'Reilly is a historical spelling variant of the Reilly name. The two share the same lineage and family affiliation; different parishes, clerks and migration registrars recorded the same name in slightly different forms, and the variant spellings sit on the same family tree.

Is Riley the same family as Reilly?

Yes. Riley is a historical spelling variant of the Reilly name. The two share the same lineage and family affiliation; different parishes, clerks and migration registrars recorded the same name in slightly different forms, and the variant spellings sit on the same family tree.

Is Ó Raghallaigh the same family as Reilly?

Yes. Ó Raghallaigh is a historical spelling variant of the Reilly name. The two share the same lineage and family affiliation; different parishes, clerks and migration registrars recorded the same name in slightly different forms, and the variant spellings sit on the same family tree.

Where is the Reilly surname found today?

Ireland is the primary historical home of the Reilly surname. In the modern era, the name is also borne across the wider diaspora, particularly in the United States, Canada, Australia and New Zealand, where families carry the line of descent from the same Ireland origin recorded on this page.

What does the Clan Rising page for the Reilly family cover?

The Clan Rising page for the Reilly family covers the meaning of the surname, the historical geography of the name, the family motto, famous bearers of the name and the seat of the head of the family. Each section is linked to the underlying atlas of Ireland so the name can be read in the geography that shaped it.

Who is the head of the Reilly family today?

The seat for the head of the Reilly family is currently vacant on this register. Clan Rising is rebuilding the chief and family structure for the modern era, and the family page allows readers to claim the seat or pledge to the name.

Neighbouring clans