The McCarthy surname
Mac Cárthaigh in Irish. ‘Son of Cárthach’, after a Munster king who died in 1045.
The MacCarthys were the leading family of Desmond – south Munster, covering much of today’s Cork and Kerry. They ruled as Kings of Desmond in the Middle Ages and split into several branches, such as MacCarthy Mór and MacCarthy of Muskerry.
The MacCarthys of Muskerry built Blarney Castle in County Cork.
Your surname is linked to the Kings of Desmond
McCarthy comes from the MacCarthy dynasty, Kings of Desmond in south Munster.
The honest caveat: A shared surname is not proof of royal descent. Thousands of McCarthys lived in Cork and Kerry by the 1800s, many unrelated in any recent way to the ruling branches. A documented tree, and Y-DNA for the male line, are the only real tests.
Other spellings to search
MacCarthy, Carthy, McCarty
Where the name is strongest
Tips for finding McCarthy ancestors
- Cork and Kerry have huge numbers of McCarthys, and nicknames (‘agnomens’) were used locally to tell families apart – look for them in the census or church records.
- The Catholic parish registers on registers.nli.ie are especially useful for Cork and Kerry families.
Start with the free official sources, or our guide to finding a grandparent’s birth record.
Sources
- Edward MacLysaght, The Surnames of Ireland
- Dictionary of Irish Biography (dib.ie), MacCarthy family entries
Surname stories are for interest. Sharing a surname is not proof of descent from anyone, and it says nothing about citizenship.