The inscription on the portal of the southern entrance (known as entrance of the "White Lions") says that the church was founded in 1137 on the site of another church from the 8th century dedicated to St Mary, which had been in turn erected over a Roman temple of the Clemence. The high altar was consecrated in 1185 and in 1187 the presbytery and the transept wings were completed. Due to financial troubles, the works dragged for the whole 13th–14th centuries. The bell tower was built from 1436 (being completed around the end of the century), while in 1481–1491 a new sacristy added after the old one had been destroyed by Bartolomeo Colleoni to erect his personal mausoleum, the Colleoni Chapel.
On the 23 of June 1449, the Senate and the Grand Council of Bergamo entrusted the management of the church to the Consorzio della Misericordia Maggiore, a prestigious association founded in 1265 by Pinamonte da Brembate, in order to preserve and enrich the artistic heritage of the Basilica. On the 14 of March 1453, Pope Nicholas V declared the church exempt from episcopal jurisdiction, and dependent on papal jurisdiction. This allowed the creation of free grammar and music schools for children in need, at the service of the liturgies in the Basilica.
In 1521, Pietro Isabello finished the south-western portal, also known as Porta della Fontana. The edifice was restored and modified in the 17th century.

https://en.wikipedia.org/wiki/Santa_Maria_Maggiore,_Bergamo

photo: Voigtlander 12mm
original size 17000x8500
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