Santa Maria Maggiore 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.
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.
The church opens on the square (Piazza Duomo) on its own left side, as the main façade has no entrance, being once united to the Bishops' Palace. The external appearance has largely maintained its Lombard Romanesque origins. The church can be accessed by two entrances by Giovanni da Campione (1353) and by Isabello's Porta della Fontana.
The main apse is crowned by a loggia surmounted by two frieze with geometrical and vegetables patterns, and has blind arcades with semi-columns. The latter's capitals have also vegetable themes, with the exception of one, decorated by Angels with Last Judgement's Trumpets. The transept's apses have a structure similar to the main one.
Notable is Giovanni da Campione's porch in the left transept, which is supported by columns departing from lions in Veronese marble. the arch has a frieze with hunting scenes, while the vault is decorated by polychrome lozenges. A loggia houses statues of St Barbara, St Vincent and St Alexander. At the peak is a Gothic niche by Hans von Fernach (1403), with the Madonna with Child flanked by St Esther and St Grata (1398). also by Giovanni da Campione is the porch of the right transept, with a similar though simpler structure. The columns are supported by lions in white marble. It has reliefs with Christ Crowned by Saints and Birth of the Baptist.
Isabello's Renaissance porch has, in the lunette, a fresco of Mary's Nativity attributed to Andrea Previtali.
The interior has maintained the original Romanesque Greek cross plan, with a nave and two aisles divided by piers and ending with an apse, but the decoration its largely from the 17th century Baroque renovation.
On the walls are tapestries, partly executed in Florence (1583–1586) under Alessandro Allori's design, partly of Flemish manufacture, depicting the Life of Mary. Over the tapestry of the Crucifixion (executed in Antwerp on Ludwig van Schoor's cartoons, 1698) is a painting by Luca Giordano, with the Passage of the Red Sea (1691).
Left to the entrance is the sepulchre of Cardinal Guglielmo Longhi, work by Ugo da Campione (1913–1320). On the rear wall are the tomb of the composer Gaetano Donizetti, by Vincenzo Vela (1855) and that of the latter's master Simone Mayr (1852). At the beginning of the left aisle is the Baroque confessional carved by Andrea Fantoni in 1704. A crucifix from the 14th century is on the presbytery's balaustrade.
In the presbytery itself, housing six bronze candelabra from 1597, is a wooden choir designed by Bernardo Zenale and Andrea Previtali. The reliefs with Biblical tales were executed in 1524–1555 on designs by Lorenzo Lotto. They are characterized by a polychrome effect rendered through the use of different wood types.
The right transepts has Giottesque frescoes from an unknown artist, with Histories of St Aegidius, The Last Supper and the Tree of Life (1347), partially covered by a 17th-century fresco.References:
Steinvikholm Castle is an island fortress built between 1525 to 1532 by Norway's last Catholic archbishop, Olav Engelbrektsson. Steinvikholm castle became the most powerful fortification by the time it was built, and it is the largest construction raised in the Norwegian Middle Ages.
The castle occupies about half of the land on the rocky island. The absence of a spring meant that fresh water had to be brought from the mainland. A wooden bridge served as the only way to the island other than boat. Although the castle design was common across Europe in 1525, its medieval design was becoming obsolete because of the improved siege firepower offered by gunpowder and cannons.
The castle was constructed after Olav Engelbrektsson returned from a meeting with the Pope in Rome, presumably in anticipation of impending military-religious conflict. As Archbishop Engelbrektsson's resistance to the encroachment of Danish rule escalated, first with Frederick I of Denmark and his successor Christian III of Denmark, Steinvikholm Castle and Nidarholm Abbey became the Catholic Church's military strongholds in Norway. In April 1537, the Danish-Norwegian Reformation succeeded in driving the archbishop from the castle into exile in Lier in the Netherlands (now in Belgium), where he died on 7 February 1538. At the castle the archbishop left behind St. Olav's shrine and other treasures from Nidaros Cathedral (Trondheim). The original coffin containing St. Olav's body remained at Steinvikholm until it was returned to Nidaros Cathedral in 1564. Since 1568 St. Olav's grave in Nidaros has been unknown.
From the 17th to 19th century, the island was used as a quarry and some of its masonry was sold and removed from the site. This activity was condoned by the Danish-Norwegian authorities as a way of eliminating a monument to the opposition of the Danish–Norwegian Union.
Steinvikholm fort is owned and operated today by The society for the Preservation of Norwegian Ancient Monuments. The island has been the site of the midnight opera which details the life and struggles of the archbishop. The opera is held in August annually. The opera is organized by Steinvikholm Musikkteater since the beginning in 1993.