[5] Due to the long delays, houses were built next to the church, taking the space originally intended for the traditional west front, which had to be relocated.

The buyer of the building returned it to the church in 1805, and the first mass was celebrated there on 10 March 1805 by Pope Pius VII, who had come to Paris the previous December to crown Napoleon Emperor.

The City of Paris purchased the building in 1817 and later a long campaign was begun to add new murals, paintings, sculpture and windows.

He sold his personal library in 1888 and used the funds to add a profusion of gilding, murals, sculptures in stucco, and the windows that are seen today.

The arcades have rounded arches and as pilasters with trompe-l'oeil channelling, joined with columns with Corinthian capitals, carved of travertine stone, and decorated with sculpted foliage and angels.

Other decoration includes a variety of sculpted sceptres, the hands of justice and other royal emblems, illustrating the association with King Louis IX.

Lehmann was a prominent figure in the school of French Romanticism"; the "Virgin and the Saints" painting was presented at the 1848 Paris Salon.

[8] -The Chapel of Baptism displays a group of eight small paintings representing scenes from the life of Christ, set into the wood panelling.

The stained glass windows mostly date to the mid-19th century; the major series, illustrating the life of Christ, are by Alfred Gérente.

This instrument, like most of the other Paris organs of the period, was destroyed during the French Revolution, to recover the lead used in the pipes to make munitions.