Ó Ceallaigh

Ó Ceallaigh
Country	Ireland
Parent house	Connachta
Titles	Kings of Uí Maine Kings of Brega Princes of Uí Maine Count Palatine of the Holy Roman Empire King-at-Arms of the Holy Roman Empire Baron of Clankelly Baron of Dungannon Counts of Gallgh and Tycooly High Treasurers of Connaught Commander of the Connaught contingent of Brian Boru's Army
Founder	Máine Mór
Final ruler	Feardorcha Ó Cellaigh
Current head	Walter Lionel O'Kelly of Gallagh and Tycooly

Ó Ceallaigh is the most influential dynasty of the ancient túath of Uí Maine, and the original Irish gaelic name for the surname commonly known as Kelly. It is a name meaning "Descendant of Ceallach," "bright haired," or "troublesome."

Ceallach was the son of Finnachta, a chief of the Hy Many people around A.D. 874. Another notable chieftain, Tadhg Mór Ó Ceallaigh, was killed at the famous Battle of Clontarf, where he and his ally Brian Boru defeated the Viking raiders.

Many members of the Ó Ceallaigh clan are directly descended from the Kings of Uí Maine (with Uí Maine commonly known as O'Kelly country), and the clan itself is the largest and senior-most ruling family of Uí Maine.

The earliest parts of the O'Kelly genealogy are contained in the Book of Hy Many, which was written in the 14th century. Its compilation was the idea of William O'Kelly, a chief of Hy Many. The book is now kept in the Royal Irish Academy in Dublin.

(Additionally, the Ua Ceallaigh are considered one of the Four Tribes of Tara.)

Counties associated with the name include:

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Wikipedia