Papers relating to the O'Connor Donelan family of Sylane, Tuam, County Galway. The papers cover the legal dealings of the family, the management of their various lands, and personal papers relating to various family members. The bulk of the personal material relates to Thomas O'Connor Donelan (1812-1874) and his sons. His eldest son Dermot had an interest in genealogy and forestry, and his other three sons were doctors in Dublin, Leeds and Manila.