The First Battle of the Marne was a significant event during World War I that played a major role in determining the course of the conflict. The battle took place from September 6th to the 12th of 1914, and it was fought between the German and French forces along the Marne River in France. The battle was a major victory for the Allies, as it was the first major Allied victory of the war, and it prevented the German advance from capturing Paris.