Robert Douglas (1594–1674) was the only minister of the Church of Scotland to be Moderator of the General Assembly five times. Robert Douglas was son of Robert Douglas, an illegitimate son of Sir George Douglas of Lochleven, brother of William, fifth Earl of Morton. He was educated at University of St Andrews, graduating with an M.A. in 1614. He was licensed as a church minister about 1617. Almost immediately afterwards he was engaged as chaplain to one of the brigades of Scottish auxiliaries co-operating with Gustavus Adolphus in the Thirty Years' War. During that period he is said to have had no other book to read but the Bible, and committed nearly the whole of it to memory.