County Leitrim is a county in Ireland. It is in the province of Connacht and is part of the Northern and Western Region. It is named after the villa…County Leitrim is a county in Ireland. It is in the province of Connacht and is part of the Northern and Western Region. It is named after the village of Leitrim. Leitrim County Council is the local authority for the county, which had a population of 35,199 according to the 2022 census.