Tuscan League

The Tuscan League, also known as the League of San Genesio, was formed on 11 November 1197 at Borgo San Genesio by the chief cities, barons and bishops of the March of Tuscany shortly after the death of Henry VI, Holy Roman Emperor on 27 September 1197.

[2][3] The original signatories were the communes of Lucca, Florence and Siena, the people living under the castles of Prato and San Miniato, and the bishopric of Volterra.

War was to be made on any city, town, count or bishop who refused to join the league when asked to do so, yet none were allowed to join without recognising their "legitimate" overlords, which in practice usually meant recognising one of the communes as lord.

[3] Shortly after the election of 1198, the new pope, Innocent III, condemned the Tuscan League as a dishonorable interference in the affairs of Tuscany, which he now claimed—on the basis of the Liber censuum (1192)—belonged entirely to the temporal jurisdiction of the Roman church.

Seven months of negotiations failed and Innocent was forced to accept the Tuscan League, even threatening Pisa with a renewed interdict.