| Parent house | Connachta (Uí Briúin Ai) becoming Mac Diarmada |
|---|---|
| Country | Kingdom of Connacht |
| Founded | 1315 |
| Founder | Donnchadh Mac Diarmada |
The surname McDonagh, also spelled MacDonagh is from the Irish language Mac Dhonnchadha, and is now one of the rarer surnames of Ireland.
Mac Dhonnchadha, Mac Donnchadha, Mac Donnacha or Mac Donnchaidh or Mac Donnacha is the original form of McDonagh
These surnames are found in their greatest numbers in Connacht (Connaught), especially the counties of Sligo, Roscommon and Galway.
Dhonnchadha, literally translated from the Irish language, means "brown warrior". The prefix mac means "son of". The MacDonaghs are renowned actors, playwrights, and revolutionaries, including the likes of Hugh MacDonagh (Actor - Evelyn), Martin McDonagh (Playwright) and Thomas McDonagh (a leader of the 1916 Easter Rising).