The Connacht Ceili Band began in 1965 as Mike McDonagh's Connacht Ceili Band. Its members had prior experience playing together for Irish social dances in and around Boston, Massachusetts. Led by accordionist Mike McDonagh, the band made an LP record in 1966 and performed regularly for Irish social gatherings in the Boston area. When McDonagh left the band in 1969, one of its founding members, accordionist Tommy Sheridan, took over the group and shortened the name to the Connacht Ceili Band. Some members continued and new musicians were added. The band made two successful tours of Ireland (the first in 1969-1970, the second in 1972), won many competitions, and performed at functions throughout the east coast of the United States. Sheridan led the group until it disbanded around 1995.