 The Württemberg territory expanded further under the rule of Ulrich III, Eberhard II and Eberhard III.Under Eberhard III, Württemberg assimilated the County of Montbéliard () through the betrothal of his son, Eberhard IV, to Henriette, Countess of Montbéliard in 1397.In 1442, the Treaty of Nürtingen was signed between Ulrich V and his brother Ludwig I.