 This presumed that Philip V would formally renounced Porto Longone, which he held, and recognised it as an imperial fief like the other "Presidi".A final treaty of peace between Charles VI, who held the coastal "Presidi", and Philip V, who retained Porto Longone, was not signed until the Treaty of Vienna of 30 April 1725.In this treaty, Charles agreed to enfeoff Don Carlos with the Duchy of Parma and Piacenza when he came of age.