The origins of the Monumental Complex ofSanto Spirito in Sassia date back to 727, when the king of the Saxons established the Schola Saxonum to give hospitality to pilgrims visiting St Peter's Basilica.
At the centre of the complex is the Ospedale di Santo Spirito, which was founded by Pope Innocent III (r. 1198-1216). By the reign of Pope Sixtus IV (r. 1471-84), the Hospital of the Holy Spirit was in a pitiful state. Sixtus IV ordered a complete rebuilding, which created the so-called Corsia Sistina, two very long halls that are separated by a chapel surmounted by an octagonal dome. The architect was Baccio Pontelli (1450-92). In 1478 the Corsia Sistina was given a series of frescoes, illustrating the history of the hospital.
In the same campaign the pope provided two cloisters for the hospital workers, one for the men and one for the women. A third cloister belongs to the Palazzo del Commendatore, the residence of the hospital's director.