 After the death of Frederick Achilles in 1631, who was still unmarried, the castle returned to the main line of the duchy.The second branch line came into existence in 1649, after the restitution of Württemberg following the Thirty Years’ War.Under the inheritance agreement of 7 October 1649 (27 September under the Julian calendar) Duke Eberhard III left his brother Frederick possession of Neuenstadt, Möckmühl and Weinsberg, although this was without sovereignty as this was passed on to Eberhard.