Saint Louis was the last of the three Charlemagne-class pre-dreadnought battleships built for the French Navy in the mid-1890s. She spent most of her career assigned to the Mediterranean Squadron and usually was chosen to serve as a flagship. The ship was involved in two accidental ramming incidents with two other French warships in her career, one of which sank a submarine.

The Charlemagne class consisted of three pre-dreadnought battleships built for the French Navy in the 1890s. The ships spent most of their careers assigned to the Mediterranean Squadron. They had oddly eventful peacetime careers as they were involved in four accidental collisions among them, one of which sank a French submarine with all hands. Saint Louis was usually a fleet flagship during her career and Charlemagne twice participated in the occupation of the port of Mytilene on the island of Lesbos—then owned by the Ottoman Empire—once as part of a French expedition and another as part of an international squadron.