Francis I, Holy Roman Emperor

Francis Stephen was the oldest surviving son of Leopold, Duke of Lorraine, and a French princess. He inherited the duchy in 1729, then married his second cousin Maria Theresa in 1736. Two years later he traded Lorraine and Bar for Tuscany as part of the settlement ending the War of the Polish Succession, handing his ancestral lands to a deposed Polish king. When Maria Theresa's father Charles VI died in 1740, the couple became rulers of the Habsburg domains; she held the real power, but gave Francis the empire's finances, which he managed well. In 1745 he was elected Holy Roman Emperor. Together they founded the Habsburg-Lorraine line. He died in 1765 and their son Joseph II took the throne, co-ruling with Maria Theresa.