The Archconfraternity of the Assunta, or Our
Lady of the Assumption, founded in 1445, was established at its
current premises in 1482. The birth of confraternities, composed of
laymen and governed by internal statutes, was one of the most
common forms of popular religiousness.
The confraternity immediately had an old medieval picture of the Madonna and Child installed on the north façade of the primitive oratory and, starting in 1483, it was thought to impart grace and work miracles. The picture was worshipped there until 1715, when it was transferred to the internal chapel while reconstruction work was carried out on the current church.
The new arrangement was based on the plans drawn
up in 1708 by the architect Giovanni Giacomo Plantery, who designed
the body of the church with curved walls in order to symbolize
hands joined in prayer. The building was constructed at the same
time as the church of the Pietà, designed by the same
architect. The two rivalling confraternities competed to build the
most prestigious premises.
Between 1714 and 1717, the interior was painted by Giovanni Battista Pozzo and his son Pietro Antonio, while the Beltramelli brothers did the stucco work. In 1717 the architect Francesco Gallo inspected the structure, and designed the choir and sacristy.
The high altar was completed in (1798) with
marble works donated by Charles Emmanuel IV, to plans by
Michelangelo Vay, and it hosts the statuary group of the Assumption
by Giovanni Battista Bernero. In 1809 the ensemble was mechanized
so it could be raised and lowered during the church functions.
What remains of the wooden decorative apparatus by the sculptor Carlo Giuseppe Plura is Christ of the Column, which is still in the oratory.
The façade we see today dates back to 1780 and is the work of Bartolomeo Maffei, in collaboration with Giuseppe Chiantore, who painted the fresco.
The bell tower, designed by Maurizio Eula in 1850, was built around 1869.