Despite enlisting in the army as a private soldier, Philippon rose to the rank of Général de Division during the Peninsular War, and was created Baron in 1809.

[5] After moving to the French Army of Hanover, Philippon was made a member of the Légion d'honneur on 19 Frimaire Year XII (November 1803) and an officer of that order on 25 Prairial (14 June 1804).

[4] He served in Spain during the Peninsular War from 1808, was created a baron in 1809,[4] and saw action with General Pierre Lapisse's division of Marshal Victor's I Corps at the Battle of Talavera and the Siege of Cádiz.

[8] In recognition of his defence of Badajoz, Philippon was promoted to major general (Général de Division) on 9 July 1811, and he remained in command of the fortress's garrison.

[5] When the town fell to the Allies on 6 April, following the Battle of Badajoz, Philippon retreated to the outlying fort at San Cristóbal, across the Guadiana river, but was forced to surrender the following day.