Frederick I, Holy Roman Emperor
The Peace of Constance (25 June 1183) was a privilege granted by Frederick I, Holy Roman Emperor, and his son and co-ruler, Henry VI, King of the Romans, to the members of the Lombard League to end the state of rebellion (war) that been ongoing since 1167. It was a permanent peace that superseded the six-year truce imposed by the Treaty of Venice (22 July 1177).