The building prior to today's church of St. Michael the Archangel was consecrated in 1038 by Bishop Hartwig. This first church was a simple, square building with a round apse on the eastern side. It was a sacred architecture in the Ottonian style of the time. The dedication to the archangel Michael, who became the Patron of the Kingdom since the victory obtained in the battle against the Hungarians in Lechfeld in 955, also dates back to the Ottonian dynasty. The troops of Emperor Otto I had in fact fought under the banner of San Michele. The Byzantine princess Theophanu, consort of Otto II and influential mother of Otto III, continued to favor the veneration of the Archangel, a native of Eastern Greece. To her the Treasury of the Cathedral owes the so-called "Chasuble of Alboino", a purple liturgical garment made with a Byzantine silk fabric bearing the image of the imperial eagle, part of Theophane's dowry. The building after this first church was later erected in the Gothic style and today still retains the appearance of the past: a late-Gothic construction built of granite blocks with pointed arched windows. The interior, on the other hand, has radically changed its face: in 1757/58 it was rebuilt in a Baroque style. Joseph Hautzinger, coming from Vienna, who had already worked in the Cathedral, created the frescoes that currently adorn the vaults of the nave.