The St. Louis Cathedral

In 1676, the Secretary of State for War, Marquis de Louvois, entrusted the young architect Jules Hardouin-Mansart with the construction of the chapel which Libéral Bruant has been unable to complete. The architect designed a building which combined a royal chapel, the "Dôme des Invalides", and a veterans' chapel achieving consistency and harmony.

In this way, the King and his soldiers could attend mass simultaneously, while entering the place of worship though different entrances, as prescribed by etiquette. This separation was reinforced in the 19th century with the erection of the tomb of Napoleon I, the creation of the two separate altars and then with the construction of a glass wall between the two chapels.

This chapel, which opens onto the main courtyard, is a good example of classical architecture. The organ case was made between 1679 and 1687 by Germain Pilon, an ordinary joiner of the Bâtiments du Roi (literally: the King's Buildings).

The cornice of the Veteran's Chapel is decorated with some hundred trophies taken from the enemy, throughout the history of the French armies, from 1805 to the 19th century. Bearing witness to age-old traditions, these trophies were hung on the vault of Notre Dame Cathedral up until the French Revolution. Those which escaped destruction were transferred to the Hôtel des Invalides from 1793. The Hôtel des Invalides was then entrusted with the mission of keeping French emblems and trophies. Nearly 1,500 of these trophies were burnt in the courtyard in 1814 by the Governor of the Hôtel des Invalides to prevent them from failing into enemy hands.

The chapel, which was dedicated to Saint-Louis and consecrated to the Holy Trinity, fell under the administrative control of the Army Museum when it was founded in 1905. It is now the cathedral for the French armies.