On 18 August, the Prussian First Army under General Karl Friedrich von Steinmetz launched its VII and VIII Corps in repeated assaults against the French positions, backed by artillery and cavalry support.

With the support of the Prussian II and Saxon XII Corps of Prince Friedrich Karl's Second Army, the Guards conquered St. Privat by 20:00 hours after heavy losses, pushing back the French right wing.

The German victory at Gravelotte ended Bazaine's army's last chance of retreating west to Verdun.

[3] They lacked efficient digging tools, but Bazaine regarded the position as virtually impregnable, with the defenders sheltered behind hedges and low walls and anchored in villages and farmhouses.

[5] Other villages that played an important part in the battle were Saint Privat, Amanweiler or Amanvillers and Sainte-Marie-aux-Chênes, all lying to the north of Gravelotte.

The mass of advancing Germans was met with murderous fire from the superior French Chassepot rifle and their rapid-firing mitrailleuses, before they were within range to retaliate with their shorter-ranged needle-guns.

[9] At 14:30, General Steinmetz, the commander of the First Army, launched his VIII Corps across the Mance Ravine but they were soon pinned down by rifle and mitrailleuse fire.

At 15:00, the massed new Krupp all-steel breech-loading guns of the German VII and VIII Corps opened fire to support the attack.

By 18:30, a considerable portion of the VII and VIII Corps panicked and disengaged from the fighting without attaining their objective and withdrew towards the Prussian positions at Rezonville.

[12] With the partial withdrawal of the First Army, Prince Frederick Charles ordered a mass artillery barrage against Canrobert's position at St. Privat to prevent the Guards attack from failing too.

General Bourbaki, however, refused to commit the reserves of the French Old Guard to the battle because, by that time, he rightfully considered the overall situation a 'defeat' having run out of ammunition, being outflanked by Prussian artillery, and losing 1/4 of his men.