He served in the Algerian campaigns from 1830 onwards, and by 1840 he had risen to the grade of maréchal-de-camp (major-general). Three years later he was made a general of division. He was one of the most distinguished and efficient of Bugeaud's generals, rendered special service at Isly (August 14, 1844), acted temporarily as governor-general of Algeria, and finally effected the capture of Abd-el-Kader in 1847.
Lamoricière took some part in the political events of 1848, both as a member of the Chamber of Deputies and as a military commander. Under the regime of General Cavaignac he was for a time minister of war. From 1848 to 1851 Lamoricière was one of the most conspicuous opponents of the policy of Louis Napoleon, and at the coup d'état of December 2, 1851 he was arrested and exiled. He refused to give in his allegiance to the emperor Napoleon III, and in 1860 accepted the command of the papal army, which he led in the Italian campaign of 1860. On September 18 of that year he was severely defeated by the Italian army at Castelfidardo.
His last years were spent in complete retirement in France (he had been allowed to return in 1857), and he died at Prouzel (Somme).
See E Keller, Le General de Lamorcière (Paris, 1873).