The surname Reely is an anglicized form of the Irish Gaelic name Ó Raghaillaigh, which originated in County Cavan, Ireland in the 12th century. The Gaelic name Ó Raghaillaigh means "descendant of Raghallach," with Raghallach being a personal name derived from the Old Norse word "Rögnvaldr," meaning "counsel-ruler."
This name was first recorded in the Annals of Ulster in 1176, which referred to a certain Máel Ísu Ó Raghaillaigh as the Chief of Muintir-Raghailligh. The Muintir-Raghailligh was a powerful Irish clan based in the territory of Cairbre Gabhra, near modern-day Cavan.
The earliest known bearer of the anglicized form Reely was Feidhlimidh Ó Raghaillaigh, who was appointed Bishop of Kilmore in County Cavan in 1349. Another notable figure was Felim Ó Raghaillaigh, who served as the Archbishop of Tuam from 1484 to 1501.
In the 16th century, the name appears in various forms in the Fiants of the Tudor Sovereigns of England, including Rely, Reyley, and Reyly. One record from 1538 mentions a pardon granted to "Ferdoragho Ó Reyly of Cavon."
The Reely surname is also found in several place names in County Cavan, such as Reelycrine, Reelygreany, and Reelysillagh, reflecting the clan's historical dominance in the region.
Notable individuals with the surname Reely include:
1. William Reely (c. 1612-1667), an English clergyman and author of "A Guide to Eternal Glory."
2. John Reely (1763-1820), an American Revolutionary War soldier and early settler of Kentucky.
3. Joseph Reely (1830-1901), an Irish-born American Civil War veteran and member of the New York State Assembly.
4. Patrick Reely (1857-1921), an Irish-born Australian politician and member of the Victorian Legislative Assembly.
5. James Reely (1894-1971), an American baseball player who played for the Boston Red Sox in the 1920s.