The Imperial Palace was constructed during the period of August Maximianus (286 AD) when Mediolanum became the capital of the Western Roman Empire. It occupied the western part of the city and it was a city in itself. It was a multifunctional structure with a full autonomy from the rest of the city. It had all the bare necessities, fittings and fixtures for the imperial court: Roman baths, religious buildings, administrative, military and residential sections. Thus, what is left to be seen in Via Brisa represents just one of many sectors of the Imperial complex.
The structure was preserved even after the seat of power moved to Ravenna (402 AD) and it was certainly used in the period when the king of the Huns, Attila conquered Milan in 452 AD. The building is believed to have been abandoned in the 10th century.
(!) The architectural remnants are visible from the street and there is no charge for visiting the site, therefore, if you happen to be anywhere near it would be a shame to simply pass by unaware of its beauty. These are just a few minutes away from the Archeological museum.