Messageries maritimes was a French merchant shipping company. It was originally created in 1851 as Messageries nationales, later called Messageries impériales, and from 1871, Compagnie des messageries maritimes, casually known as "MesMar" or by its initials "MM". 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 . In 1977 it merged with Compagnie générale transatlantique to form Compagnie générale maritime. In 1996 CGM was privatized and sold to Compagnie Maritime d'Affrètement (CMA) to form CMA CGM.
In 1851 a ship owner from Marseille, Albert Rostand, proposed to Ernest Simons, director of a terrestrial carrier company, the Messageries mationales, to merge to create a shipping company, first called Messageries nationales, then Messageries impériales, and finally in 1871 the Compagnie des messageries maritimes. Two engineers, Henri Dupuy de Lôme and Armand Béhic joined the company, encouraging the purchase of the shipbuilding yards of La Ciotat in 1849.
In the beginning the Company operated on routes to the Middle East. 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. This was the first French transatlantic line equipped with steamers. The following year, the Société générale maritime (future Compagnie générale transatlantique) received the North Atlantic lines.
From 1871 to 1914 the Compagnie des messageries maritimes saw its golden age. This was the period of French colonial expansion and of interventionism in the Middle and Far East. The Marseille liners continuously served in the Mediterranean Sea, the Black Sea, then the Red Sea, the Indian Ocean, the China Sea and finally the Pacific Ocean. In the west, the South Atlantic line filled out. Even the North Atlantic knew the ships with the typical double funnel, which worked the route London – Dunkirk – Le Havre – Marseille. In the Middle East, the ports of call were Malta, Alexandria, Port Said, Beirut, Syria, Smyrna, Constantinople, and the Black Sea. In the Indian Ocean, the line served Mahé, Seychelles, La Réunion, Mauritius, Zanzibar and Madagascar as well as the French establishments in India. At Pondicherry the small harbour necessitated the use of ship's tenders.