Rathcline barony was formed from the territories of The Callow and the territory of Clanconnor. Rathcline Castle was built around the 9th Century by the Ó Cuinn clan. Later it was fought for and taken by the Uí Fhearghail clan and subsequently taken over by the Normans around the beginning of the 12th Century. Ó Fachtna is also noted as chief of the Callow into the 16th century.