O’Sullivan – descendants of 3rd century royalty

O’Sullivan is the third most popular surname in Ireland and the most common to have reinstated the Gaelic ‘O’ prefix to the name.

The O’Sullivans originally come from the Munster region of Ireland. They are descended from Eoghan Mor, whose son Olioll Olum was the King of Munster in the 3rd century.

Back to Irish surnames

History of the Irish name O'Sullivan. Image copyright Ireland Calling
Eoghan Mor is also an ancestor of the MacCarthys, O’Keeffes and O’Callaghans.

Dark eyed or one eyed?

The name O’Sullivan derives from O’Sileabhin. The word ‘sil’ means eye and scholars believe that O’Sileabhin means either ‘one eyed’, ‘dark eyed’ or ‘hawk eyed’.

In the 1100s, the O’Sileabhins were Lords in Cahir, County Tipperary. They later split into two septs and spread further afield. The O’Sullivan Mor sept settled in what is now South Kerry and the O’Sullivan Beare went to West Cork.

The motto on the O’Sullivan coat of arms reads ‘Lam Foisteanac Abu’ which means ‘The steady hand to victory’.

Video of the story of the O’Sullivan name

Rebellion against Queen Elizabeth I

In 1602 Donal O’Sullivan Beare joined forces with the O’Neills and led his clan in the rebellion against Queen Elizabeth I. They had been supported by the King of Spain. However, Spanish general Juan del Águila, surrendered.

O’Sullivan elected to fight on and his men were under siege at Dunboy Castle, but they were able to withstand the attack.

O’Sullivan then led them 200 miles to safety in the territory of his allies, the O’Rourkes. Many of the men died of starvation or in battles during the journey but O’Sullivan is still seen as a hero for his resistance to the Queen’s army.

He later took many of his family members to Spain after being invited by King Philip III. Many O’Sullivans served in the Spanish army and navy.

He is the first person with the name O’Sullivan to be recorded in writing. His exploits were noted in the book ‘Records of Dunboy, Bantry Bay’.

Owen Roe O’Sullivan

The poet Owen Roe O’Sullivan was born in 1748. He was a talented songwriter and poet but had to flee to England when he was caught having an affair with a married woman. He joined the British navy but regretted doing so and often tried to leave.
Ronnie O'Sullivan. Photo copyright Anne Marie Forker CC3
Despite this he was an excellent navy man and was commended for his bravery during battles with the French. Ironically, his death came in a fight, not against the French military but with servants of Captain Cronin who had been the subject of criticism in O’Sullivan’s poetry.

Famous O’Sullivans throughout the world

Katherine D Sullivan, from Paterson, New Jersey, became the first American woman to walk in space on 11th Oct 1984. She was part of STS-41-G, which was the 13th flight of NASA’s space shuttle program. It was also the first mission to involve two women on the crew.

The first heavy weight boxing champion of the world was ‘Boston Strong Boy’ John L Sullivan. World titles didn’t exist when he was active and he was honoured as the first World Champion many years later for his defeat of Charley Mitchell in 1888.

Ronnie O’Sullivan was born in Essex, England. He is a five time world snooker champion and is considered by many experts to be the most naturally gifted player of all time.

Back to Irish surnames

Great Celtic art available in our store - Personalised prints

Your name in Ogham. Personalised artwork

Loads more products and designs available

Do you qualify to become an Irish citizen?

There are three main ways for a person to qualify for Irish citizenship – through birth, through marriage or civil partnership or through naturalisation. Check if you qualify for Irish citizenship

Did you know?

Singer songwriter Ed Sheeran performed an Irish language version of his smash single Thinking Out Loud on RTÉ 2fm. It was a great gesture from Sheeran to learn his own song in another language – and his performance came after a classic radio prank. Find out more.

Have you heard about…

A stunning former schoolhouse in Co Sligo was sold in 2017 and turned into a beautiful home. Take a look inside.

What about this…

‘The man who couldn’t be killed’ - firefighter Mike Molloy was an Irish emigrant living in New York in the early 20th century. He was the victim of a consistent series of murder attempts by an insurance fraud gang. Find out more.


Copy Protected by Chetan's WP-Copyprotect.