At Frankenthal in 1796 he won the Military Order of Maria Theresa. In the campaign of 1800 he distinguished himself greatly as a cavalry leader at Marengo (14 June), and in the next year became major-general. In the war of 1805 he was again employed in Italy and won further renown by his gallantry at the battle of Caldiero. In 1809 he again saw active service in Italy under the Archduke John in the rank of lieutenant field marshal, serving in Chasteler's Corps at 1st Sacile 15–16 April, and Caldiero (Soave). He commanded the rearguard at the Piave, but was defeated at 2nd Sacile and at Saint Daniel 11 May. He commanded the Reserve Corps at the Battle of Raab 14 June. In 1812 Frimont led the cavalry of Schwarzenberg's corps in the Russian campaign, serving at the action at Gorodetschna (Podobna, Prujany) 12 August. He replaced Schwarzenberg as commander in January 1813.