What is the origin of the last name Oneill?

The last name O'Neill originates from Ireland and is one of the most prominent Irish surnames. Derived from the Gaelic name Ui Néill, meaning "descendant of Niall," it traces its roots to the ancient high kings of Ireland, specifically the dynasty attributed to Niall of the Nine Hostages. The O'Neills played a significant role in Irish history, serving as chieftains and leaders of the powerful Kingdom of Ailech in Ulster.

Countries of origin for the last name Oneill

The last name Oneill, also spelled O’Neill, is an Irish surname with a rich history and significant meaning. It is derived from the Gaelic name Ó Néill, which means “descendant of Niall.” This surname has been prominent in Irish history and culture for centuries, and it continues to be a common surname in Ireland and throughout the Irish diaspora.

The name Niall, from which the surname Oneill is derived, is of ancient Celtic origin and has roots in the Old Irish word “niadh,” meaning “champion” or “cloud.” The name Niall was borne by several legendary figures in Irish mythology, including Niall of the Nine Hostages, a powerful High King of Ireland in the 5th century. The fame and influence of these historical figures contributed to the significance and popularity of the surname Oneill.

The Ó Néill clan, associated with the surname Oneill, can trace its origins back to the 5th century. They were the most powerful aristocratic family in medieval Ireland and held the title of Kings or High Kings of Ireland for centuries. The Ó Néill clan was known for their military prowess, leadership, and political influence. Their stronghold was in the province of Ulster, specifically in what is now Northern Ireland.

During the Anglo-Norman invasion of Ireland in the 12th century, the power and influence of the Ó Néill clan faced significant challenges. However, the clan managed to maintain its prominence and continued to play a significant role in Irish history and politics. The surname Oneill spread throughout Ireland during this time as members of the clan settled in various regions, establishing branches and spreading their name.

Over the centuries, many individuals with the surname Oneill have made notable contributions in various fields. These include art, literature, politics, and military service. The surname’s endurance and continued prominence in Irish culture and heritage attest to its importance and the pride that individuals with this name feel.

Today, the surname Oneill is quite common in Ireland and among the Irish diaspora. Many individuals with this surname can be found in the United States, Canada, the United Kingdom, and Australia, among other countries. The widespread presence of Oneills worldwide reflects the historical and ongoing migration of the Irish people.

In conclusion, the last name Oneill is a significant Irish surname derived from the Gaelic name Ó Néill. It has a deep-rooted history connected to powerful figures in Irish mythology and the Ó Néill clan, who held remarkable influence in Irish society for centuries. The enduring presence of Oneills both in Ireland and throughout the world bears testament to the significance and pride associated with this surname.

Interesting facts about the last name Oneill

  • The surname O’Neill is of Irish origin, and it is one of the most prominent and ancient surnames in Ireland.
  • The name O’Neill, derived from the Irish Ó Néill, translates to “descendant of Niall.” It is believed to have originated from the Ui Néill dynasties, which played a significant role in Irish history.
  • The O’Neills were one of the most powerful and influential families in Ireland for centuries. They were the ruling dynasty of the ancient kingdom of Tyrone and played a central role in Irish politics and conflicts.
  • The surname O’Neill has numerous variations and anglicized spellings, including O’Neill, O’Neil, Neill, and Neil. These variations often resulted from different transliterations from Irish Gaelic to English.
  • Famous historical figures with the surname O’Neill include Hugh O’Neill, known as “The Great Earl,” who was a prominent figure in the Nine Years’ War against English rule in Ireland.
  • Many O’Neills emigrated from Ireland to various parts of the world, particularly during the Irish diaspora in the 19th and 20th centuries. As a result, the surname can be found in countries such as the United States, Canada, Australia, and the United Kingdom.
  • The O’Neill family motto is “Lámh Láidir An Uachtar” in Irish, which translates to “The Strong Hand from Above.”
  • The O’Neill coat of arms features a red shield with a silver (or white) diagonal band running from the top right to the bottom left. Above the band, there are nine red roses, symbolizing the nine original counties of Ulster.

Name Rank


There are around 50028 people with the last name Oneill in the US

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