The name Cullen has its roots in the Gaelic language, originating from the Celtic regions of Ireland and Scotland. It is derived from the Irish Gaelic word "cuil," meaning "angle" or "corner," and the suffix "-an," indicating a diminutive form. The name likely referred to someone who lived in a remote or secluded area.

One of the earliest recorded instances of the name Cullen can be found in the Annals of Ulster, an ancient chronicle of medieval Irish history, where it is mentioned as a personal name in the 12th century. The name gained popularity in Ireland and Scotland during the Middle Ages and was often associated with families of Gaelic descent.

In the 13th century, a prominent Scottish nobleman named Cullen of Buchan is mentioned in historical records. He was a supporter of King Alexander III of Scotland and played a significant role in the political affairs of the time. Another notable figure bearing the name Cullen was Saint Cullen of Boyle, an Irish monk who lived in the 7th century and founded a monastery in County Roscommon, Ireland.

During the Renaissance period, the name Cullen was associated with several scholars and intellectuals. One such figure was Patrick Cullen (1503-1565), an Irish Franciscan friar and theologian who served as the Bishop of Clogher and played a prominent role in the Catholic Church's response to the Reformation.

In more recent times, the name Cullen has been carried by several notable individuals, including:

1. Thomas Cullen (1868-1953), an American gynecologist and pioneering cancer researcher who developed the Cullen's sign, a diagnostic tool for identifying ruptured ectopic pregnancies.

2. Countee Cullen (1903-1946), an influential African American poet and a leading figure of the Harlem Renaissance literary movement.

3. Cullen Jones (born 1984), an American swimmer and Olympic gold medalist who specialized in freestyle and butterfly events.

4. Cullen Bunn (born 1971), an American comic book writer known for his work on titles such as Uncanny X-Men, Deadpool, and Venom.

5. Cullen Douglas (born 1943), an American actor best known for his roles in television shows like Seinfeld and The Twilight Zone.

The name Cullen has maintained a consistent presence throughout history, with its origins rooted in the rich cultural heritage of the Celtic regions. While its popularity may have ebbed and flowed over time, it has left an indelible mark on various aspects of society, from literature and scholarship to sports and entertainment.