The First Battle of Marne was fought in September 1914 and followed the Battle of Mons, which had taken place in August.
The war of movement had lasted just one battle in World War One before it turned to trench warfare. The Germans had entered Europe in August in accordance with the Sclieffen Plan, which had ordered fast movement through the area.
Initially, this approach went relatively well as the Belgian Army was quickly defeated at the British Expeditionary Force (BEF) retreated at Mons. Sir John French, commander of the BEF, had requested permission to retreat to the coast but this had been rejected by Lord Kitchener, who stated that they should remain in contact with the French Army as they retreated to the Marne River.
It was here that the German and French armies fought the first major battle on the Western Front. Under the command of Joseph Joffre, the French Army reached an area south of the Marne River. While not very fit for battle, Joffre decided that the best form of defence for the army was to attack, and he ordered an attack on the German First Army.
On 6th September 1914, 150,000 French soldiers of the Sixth Army attacked the right flank of the Germans, creating a large split between the German army as the remainder attempted to attack Paris.
The gap, of around 45km, was then exploited by the French Fifth Army and the BEF. However, the Germans still held the momentum and the Sixth Army would have almost certainly been defeated that they not transported 6,000 infantry reservists to the front line via taxi.
The French Army continued to increase the gap between the German First and Second Armies, which further damaged communications between the two German flanks. As a result, Von Moltke, German Chief of Staff, was concerned that the Allies were in the position to defeat the German armies that were moving towards Paris. As such, on 9th September he ordered them to retreat and withdraw to the River Aisne. This is where the Germans first dug into trenches, which were set to dominate the entire war.
The Battle of the Marne followed, and was very costly in terms of lives and injuries. Around 250,000 French soldiers were lost during the battle and the Germans suffered similar numbers of casualties. However, the BEF lost fewer than 13,000 men.
The Schlieffen Plan was now officially ruined, and trench warfare was set to dominate the coming years across the Western Front.
"The First Battle of the Marne". HistoryLearning.com. 2019. Web.