He studied at the French military academy Saint-Cyr and was commissioned a lieutenant in the 2nd Light Infantry Regiment in 1824.

Forey soon commanded a brigade and in 1852, and was promoted to général de division for having supported Napoléon III in his coup d'état.

[2] During the Crimean War, Forey commanded a division with which he served in the siege of Sebastopol.

During the Franco-Austrian War of 1859, Forey commanded the 1st Infantry Division with which he saw action at the battles of Montebello and Solferino, where he distinguished himself in breaking the last Austrian positions near the village of Cavriana.

Having been made a senator after the end of the war, Forey was named commanding general of the French expeditionary corps to Mexico in 1862.