William I of Geneva (c. 1132 – 25 July 1195) was Count of Geneva from 1178 to 1195, in succession to his father, Count Amadeus I of Geneva. William's mother was Amadeus' wife, Matilda de Cuiseaux. * His first wife was Marguerite Beatrice de Faucigny, by whom he had three children: * * Marguerite of Geneva, wife of Thomas I of Savoy * William II of Geneva * His second wife was Agnes of Savoy, daughter of Amadeus III of Savoy, by whom he had one daughter: * Beatrice of Geneva * His third marriage, to Beatrice de Vaupergue, was childless. He died at the Château de Novel in Annecy, France.