The given name Kerrigan has its origins in the Gaelic language, derived from the Irish surname Ó Ciarghráin, which means "descendant of Ciarghráin." The name Ciarghráin itself is a combination of the Gaelic elements "ciar," meaning "black" or "dark," and "grán," meaning "grain" or "seed."

This name is believed to have originated in Ireland, specifically in the regions of County Mayo and County Sligo, where it was first recorded as a surname in the 12th century. The earliest documented use of Kerrigan as a given name dates back to the 16th century.

In Irish mythology, there are references to a figure named Ciarán of Saigir, who was a prominent saint and one of the Twelve Apostles of Ireland in the 5th century. While not directly related to the name Kerrigan, this association with an important religious figure may have contributed to the name's popularity in Ireland.

One of the earliest recorded individuals with the name Kerrigan was Kerrigan O'Reilly, an Irish chieftain who lived in the 16th century and played a significant role in the Irish Confederate Wars of the 1640s.

Other notable individuals with the name Kerrigan throughout history include:

1. John Kerrigan (1768-1847), an Irish-American soldier who fought in the American Revolutionary War and the War of 1812.
2. Kathleen Kerrigan (1886-1975), an Irish actress and theater manager who co-founded the Abbey Theatre in Dublin.
3. Joseph Kerrigan (1904-1973), an American Catholic bishop who served as the Bishop of Santa Rosa, California, from 1962 to 1973.
4. Marcia Kerrigan (1928-2008), an American actress known for her roles in television shows such as "The Untouchables" and "Perry Mason."
5. John Kerrigan (born 1952), an English literary critic and academic who has written extensively on Shakespeare and Renaissance literature.

While the name Kerrigan has been more commonly used in Ireland and among Irish communities around the world, it has also gained popularity in other English-speaking countries, particularly in the United States and Australia, where it is often associated with Irish heritage and culture.