First Battle of Buzenval (or Montretout)

The First Battle of Buzenval, also called the Battle of Montretout, was a sortie by the besieged French army of Paris against Prussian troops. General Ducrot attempted a breakthrough westward to disrupt enemy lines around Fort Mont Valérien. The French offensive temporarily captured Buzenval, but Prussian counterattacks drove French troops back inside Paris's defensive lines.

After the fall of Sedan, Paris had been besieged since September 1870. The Government of National Defense attempted to maintain pressure on the besiegers through regular sorties. That of 21 October, led by General Ducrot, aimed to loosen the Prussian grip west of the capital, toward the Bois de Boulogne and Saint-Cloud. It was one of the first major attempts to break the siege.

French forces advanced in several columns from Mont Valérien toward the villages of Buzenval, Montretout, and Garches. French artillery bombarded Prussian positions before the assault. Infantry advanced through the woods, supported by mobiles and marching battalions. After an initial advance, French troops were driven back by a powerful Prussian counteroffensive that recaptured lost ground.

The defeat at Buzenval showed the limits of the Parisian army's offensive capabilities. Although French soldiers showed bravery, lack of coordination and Prussian tactical superiority prevented any lasting breakthrough. The battle did not loosen the capital's encirclement. It heralded a series of failures of Parisian sorties during the winter of 1870–1871.