[b] Back at Lorient on 25 June 1793, Lemarant studied to be admitted as a naval student 2nd class.
The frigate sailed to Cayenne, and on 17 December 1799 on her journey back captured HMS Calcutta, a former East Indiaman.
He stayed in the Indian Ocean until August 1804, before returning to France, where he was notified of his promotion to Lieutenant on 26 October 1803.
In July 1808, Lemarant de Kerdaniel was promoted to Commander, and served as an aid to minister Denis Decrès.
At the Bourbon Restoration, Marengo was used as a troop ship to ferry the soldiers that were to take back possession of Martinique and Guadeloupe.
Back to Brest in 1815, Lemarant refused to take any part in the Hundred Days, but was nevertheless sidelined by the Bourbons until 1817, when he was given command of Hector.
In 1823, captaining the frigate Guerrière, he cruised off Spain during the invasion by the Hundred Thousand Sons of Saint Louis.