It was founded in the seventh century, during the reign of the Lombard king Cunipert between 679 and 700 by the noble Gregorius[1] and housed a chapel (or oratory) dedicated to Saint Michael (demolished in 1867, whose remains were object of an archaeological investigation in the 1970s).

[9] The monastery was almost entirely rebuilt in the fifteenth century in Gothic and Renaissance forms and of the previous Lombard age complex, only some elements incorporated in subsequent constructions remain.

In the northern part of the cloister you can see, inserted in the masonry, the remains of the massive bell tower (dating back to the Lombard age[11]) of the oratory of San Michele alla Pusterla, characterized (in the surviving portion) by decorations with brick crosses in relief.

[12] The east side of the cloister gives access to the small church of the Savior, also from the 15th century, with a Greek cross, with central and corner domes, covered like the walls with frescoes by Bernardino Lanzani.

The chapel, with five domes, a typically Byzantine detail, perhaps influenced by the institution's dependence on the Paduan congregation, is articulated around four columns, while below, there is a crypt that reproduces the same plant.

Originally, the building probably housed the large crucifix in silver foil, commissioned between 963 and 965 by the Abbess Raingarda and now preserved in the left transept of the basilica of San Michele.