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County Roscommon

Contae Ros Comáin · Connacht
The O'Conor kingdom — ancient Connacht heartland, Shannon lakes, and the county of Ireland's last High Kings

Common Surnames from County Roscommon

The most frequent family names with roots in County Roscommon — names that spread through Ireland and the Irish diaspora:

O'Conor McDermott Flanagan Tiernan Kelly Murray Brennan Flynn

History & Heritage

County Roscommon is the heartland of ancient Connacht and home to the O'Conors — the most powerful Gaelic dynasty in Ireland after the Normans. Cathal Crobderg O'Conor, King of Connacht, founded Roscommon Abbey in 1253. His descendants include the O'Conor Don and O'Conor Roe branches, both of which survived into the modern era as Catholic gentry families.

Rory O'Conor was the last High King of Ireland — the last Ard Rí to exercise genuine authority over the island. Deposed by the Norman invasion in the twelfth century, his abdication (technically his submission to Henry II in 1175) marked the end of the native Irish kingship.

The county's landscape is shaped by the Shannon lakes — Lough Ree forms much of its eastern border. The drumlin country of the north gives way to the limestone plain of the south, where the great abbeys and castles of the O'Conor kings still stand.

The County Roscommon Diaspora in America

Roscommon had some of the highest emigration rates in Ireland during the Famine period. The county's population fell by over 40% between 1841 and 1851. Roscommon families went heavily to New York, Boston, and Liverpool, and later to Chicago and Boston's South Side.

Stay Connected to County Roscommon

Love Ireland covers Roscommon's Connacht heritage, the Rindoon medieval settlement on Lough Ree, Roscommon Castle, and the lake landscapes of the Shannon corridor.

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Researching Your County Roscommon Ancestry

If your family came from County Roscommon, here's where to start your research:

Notable People from County Roscommon

Related Irish Surname Guides

Common County Roscommon surnames with dedicated pages on this site:

Kelly Brennan Flynn Murray