[3] Fantassin carried enough fuel oil to give her a range of 1,520 nautical miles (2,820 km; 1,750 mi) at a cruising speed of 10 knots (19 km/h; 12 mph).

[2] The primary armament of the Chasseur-class ships consisted of six 65-millimeter (2.6 in) Modèle 1902 guns in single mounts, one each fore and aft of the superstructure on the centerline and the others were positioned nearby.

[4] Fantassin was ordered from Forges et Chantiers de la Méditerranée on 30 October 1907 and was laid down later that year at its shipyard in Le Havre-Graville.

[5] Together with her three sister ships, Chasseur, Cavalier, and Janissaire, she was scheduled to participate in a large naval review by the President of France, Armand Fallières, off Toulon on 2 September 1911 after the annual fleet maneuvers.

[5] When the First World War began in August 1914, Vice-Admiral (Vice-amiral) Augustin Boué de Lapeyrère, commander of the 1st Naval Army, was tasked to prevent the Austro-Hungarian Navy from leaving the Adriatic Sea and breaking their blockade of Antivari (now known as Bar).

Fantassin, her sister ship Cavalier, the destroyer Bouclier and the armored cruiser Jules Ferry responded, but were unable to render assistance due to the heavy weather.

[10] Fantassin was badly damaged when the French destroyer Mameluck accidentally rammed her in the Ionian Sea at 02:30 on 5 June 1916 while the two ships were patrolling the Otranto Barrage 14 nmi (26 km; 16 mi) west of the Greek island of Othonoi.