On 22 April 1459, Pope Pius II issued the bull "Triumphans Pastor", in which he raised the diocese of Siena to metropolitan status, and assigned to it as suffragans the dioceses of Soano, Chiusi, Massa, and Grosseto.: "Necnon filias nostras praedictas Suanensem, Clusinensem et Grossetanensem et Massanensem Ecclesias, cum suis civitatibus et dioecesibus, iuribus el pertinentiis universis, Ecclesiae Seuensi et arcbiepiscopis praefatis, tamquam illorum metropolitanis et de eorum provincia...." On 13 August 1462, with the bull "Pro Excellenti", Pius II created a new diocese, the diocese of Pienza, with his native town as the seat of the bishop. Territory for the new diocese came in part from the diocese of Chiusi.Bullarum diplomatum et privilegiorum sanctorum romanorum pontificum V, pp. 166-169, at p. 167 §3: "ac arcem Tentinnam, cum Balneis Avinianis, Castilionis, Vallis Urciae, Campigliae, cum Balneis S. Philippi, Sancti Petri in campo Continiani, Perignani, Castri veteris, Montis Nigri, Sancti Angeli in colle, Castri Novi Abbatis, Seggiani, Ripae,Vinionis, Monticchielli et Fabricae, quae hactenus Clusinae dioecesis fuerunt, ab ipsa Clusina...."
