Province of Ulster

County Cavan

Known as The Breffni County. For Bréifne, the kingdom that covered Cavan and Leitrim under the O'Rourkes and O'Reillys. The county is younger than the kingdom it is named for.

Did you know? The mighty Shannon begins as a quiet pool on the slopes of Cuilcagh — the Shannon Pot, where the goddess Sionann was said to have drowned seeking forbidden wisdom.

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Through the ages — who held Cavan

8,000 BC – 4,001 BC Mesolithic hunter-gatherers The First Irish

4,000 BC – 2,501 BC Neolithic farming communities The Tomb Builders

2,500 BC – 501 BC Bronze Age Ireland The Age of Gold & Bronze

500 BC – AD 99 Iron Age Ireland The Iron Age

AD 100 – AD 399 Erdini Ptolemy's Ireland

AD 400 – 1013 The Connachta The Five Fifths Patrick & the Rise of the Uí Néill Saints & Scholars The Viking Storm Norse Cities & the Rise of Brian

1014 – 1333 Bréifne (O'Rourke) Kings with Opposition The Norman Invasion High Tide of the Colony

1334 – 1607 East Bréifne (O'Reilly) The Gaelic Resurgence The Kildare Ascendancy The Tudor Conquest

1608 – 1640 Plantation counties The Plantation of Ulster

1641 – 1652 Confederate Ireland Confederate Ireland & Cromwell

1653 – 1800 Kingdom of Ireland Ascendancy Ireland

1801 – 1915 United Kingdom of Great Britain & Ireland The Act of Union An Gorta Mór — The Great Famine Land & Liberty

1916 – 1921 Irish Republic (declared, contested) The Revolution

1922 – 1936 Irish Free State Partition — Free State & Northern Ireland

1937 – 1948 Ireland (Éire) Éire

1949 – 2026 Republic of Ireland The Republic & the Troubles Peace & the New Ireland

Clans & surnames of Cavan

Adams Mac Ádhaimh Ulster Scots / Gaelic · “son of Adam” Brady Mac Brádaigh Gaelic sept · “son of Brádach, 'spirited'” Clarke Ó Cléirigh Gaelic learned family · “descendant of the cleric — possibly Europe's oldest surname (916 AD)” Comiskey Mac Cumascaigh Gaelic sept · “son of Cumascach, 'the confuser' or 'mixer'” Dolan Ó Dobhailen Gaelic sept · “descendant of Dobhailen” Farley Ó Faircheallaigh Gaelic sept · “descendant of Faircheallach” Finnegan Ó Fionnagáin Gaelic sept · “descendant of Fionnagán, 'little fair one'” Fitzsimons Mac Síomóin Norman · “son of Simon” McCabe Mac Cába Scots-gallowglass · “son of Cába” McGovern Mág Shamhradháin Gaelic sept · “son of Samhradhán, 'summer's child'” Nugent Nuinseann Norman · “from Nogent in France” O'Donoghue Ó Donnchadha Gaelic dynasty · “descendant of Donnchadh” O'Reilly Ó Raghallaigh Gaelic sept · “descendant of Raghallach” O'Rourke Ó Ruairc Gaelic dynasty · “descendant of Ruarc (a Norse name)” Sheridan Ó Sirideáin Gaelic sept · “descendant of Sirideán, 'the seeker'” Smith Mac Gabhann Gaelic sept · “son of the smith” Tully Mac an Tuile / Ó Maoltuile Gaelic learned family · “son of the flood — 'of God's will'”

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On the ground in Cavan

Calf House · dolmen
Drumlane · round tower · incomplete · 12 m
Finn McCools Fingers · tomb
3 castles · Bailieborough Castle, Cabra Castle, Castle Saunderson

Every pin is placed by its documented coordinates. All the monuments of Ireland →

Quick answers

What is the Irish name for County Cavan?

An Cabhán. Cavan is one of the 9 counties of Ulster (Cúige Uladh).

Who ruled County Cavan in the Middle Ages?

Around 1014 it was held by Bréifne (O'Rourke); by 1450, East Bréifne (O'Reilly). The full era-by-era chronology is on this page.

What surnames come from County Cavan?

Names historically associated with Cavan include Adams, Brady, Clarke, Comiskey, Dolan, Farley, Finnegan, Fitzsimons, among others.

Trace your ancestors in Cavan

Free, from the holding institutions. How to begin: the six-step guide → · Spotted an error on this page? Suggest a correction.