Called by the pope to the apostolate, the Augustinians left their hermitages for the city, following the Friars Minor and the Preaching Friars into the scholastic world of the university. This is not a case of actually abandoning the centers of their origin, which, as documents attest, continued their activity and, reinforcing their relations with Siena, grew in importance.
Bandini dei Balzetti da Siena, prior from 1227 to 1276 of the hermitage of San Salvatore at Lecceto, was responsible for introducing the Augustinian order into the city of Siena. At first the Augustinians stayed near Porta Laterina in the modest quarters of the institute of San Giovanni or of the Santa Trinità, which earlier had already housed a universitas heremitarum.
Around the middle of the thirteenth century, as a result of the purchase of some land just below the Porta all’Arco, on the Sant’Agata hill, the monks, with the support of the communal government, began building a new convent, which was finished around 1310.
The completion of this new institution marked also a change in the ideological outlook of the friars who, breaking away from just hermitic contemplation, embraced the necessity of the apostolate.