Its rectangular house flag, with the letters MM on a white background and red corners, was famous in shipping circles, especially on the Europe-Asia trade lanes .

Two engineers, Henri Dupuy de Lôme and Armand Béhic joined the company, encouraging the purchase of the shipbuilding yards of La Ciotat in 1849.

Its ships were used as troopships during the Crimean War, and were so helpful for the army that the Emperor gave the company the right to operate on the Bordeaux – Brazil route as thanks.

Their performance was of such interest to the British Royal Navy that the Jerseyman Edouard Gaudin, who could pass for French, was sent to investigate their use.

[2] Even the North Atlantic knew the ships with the typical double funnel, which worked the route London – Dunkirk – Le Havre – Marseille.

In the Indian Ocean, the line served Mahé, Seychelles, La Réunion, Mauritius, Zanzibar and Madagascar as well as the French establishments in India.

[1][3] In 1912, the company lost its exclusive right to carry French mail on South American routes to Compagnie de Navigation Sud-Atlantique.

The ship that were loss in the war were replaced by larger and more luxurious liners and the newly opened Panama Canal was added to the route network at the beginning of the 1920s.

They had the largest fleet of ships under one flag, with nine combination passenger/cargo liners built in the 1950s for routes across Europe and Africa to areas containing commercial or cultural interests for France's citizens.