La Marseillaise is the official French National Anthem. The origins of La Marseillaise are curious:

In 1792 France declared war on Austria and Prussia. Claude Joseph Rouget de L'Isle, an engineer in the French army who was stationed in the French city of Strasbourg, had been asked by the mayor to write a marching tune for the troops. Originally entitled "Chant de guerre de l'armeé du Rhin" (War Song of the Army of the Rhine), the song quickly became popular with the volunteer army units from the French city of Marseilles, and was henceforth dubbed "La Marseillaise",and became the offical French National Anthem.