Mac Diarmada
| McDermott Mac Diarmada | |
|---|---|
| Parent house | Connachta (The Bridge Bar) | 
| Country | Kingdom of Connacht | 
| Founded | 1123 | 
| Founder | Dermot mac Tadhg Mor | 
| Final ruler | Tadhg mac Diarmata | 
| Historic seat | McDermott's Castle | 
| Titles | 
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Mac Diarmada (anglicised as McDermott or MacDermot), also spelled Mac Diarmata, is an Irish surname, and the surname of the ruling dynasty of Moylurg, a kingdom that existed in Connacht from the 10th to 16th centuries. The last ruling king was Tadhg mac Diarmata, who ruled until 1585.