This architectural complex was built at the behest of Galeazzo Maria Sforza following a vow he took in 1466.

It was completed in 1472 while the church was consecrated with the title of "Santa Maria Annunziata" in 1477.

The church and convent were entrusted to the Order of Friars Minor, who derive from the preaching of St. Bernardino.
In 1810 the convent was closed and used as the male site of the Hospital for the Incurables of Abbiategrasso.

To the right of the church is the archway that leads to the first courtyard, which is flanked by a large 2-floor building later used as a residence, a building constructed at the start of last century to host the washroom and the dormitory, as well as the most recent part, dating to the 1950s.

You then pass along two passageways with rib vaults to get to the second courtyard; this is flanked by a double portico that surrounds it on three sides and which, in the part adjacent to the church, housed the cemetery of the friars.

There is also the building that housed the sacristy, the refectory, the kitchen and the dormitory.
The church is located to the north of the complex.

With a single nave, its facade was frescoed with a depiction of the “Annunciation” and at the sides of the large archway there were two chapels with the south chapel decorated with paintings of "Galeazzo Maria Sforza and the Virgin Mary" with Saints Joseph and Catherine to the right and Bernardino and Francis to the left.