George Sinclair, 5th Earl of Caithness  George Sinclair, 5th Earl of Caithness (d. 1643) was a Scottish nobleman and chief of the Clan Sinclair, a Highland Scottish clan in Caithness. George Sinclair, 5th Earl of Caithness was the eldest son of John Sinclair, Master of Caithness and his wife Jean, daughter of Patrick Hepburn, 3rd Earl of Bothwell. His father, the Master of Caithness, had obtained a charter from Mary, Queen of Scots by which the Earldom of Caithness became a "male fee", to him and his male heirs. George Sinclair, 5th Earl of Caithness therefore succeeded his grandfather, George Sinclair, 4th Earl of Caithness in 1583. He was Sheriff of Caithness. This led to a dispute with George Keith, 5th Earl Marischal in 1610 because his tenants in Caithness were not subject to the Sheriff's jurisdiction. After a law suit from George Sinclair of Dunbeath, Marischal sold his Caithness lands to the Earl. George Sinclair, 5th Earl of Caithness married Jean Gordon, daughter of George Gordon, 5th Earl of Huntly and Anne Hamilton and had the following children: