Amiral Duperré was ordered as part of a French naval construction program aimed at countering the growth of the Italian fleet, which had begun work on the very large ironclads of the Duilio and Italia classes in the early 1870s.

By the late 1890s, more modern pre-dreadnought battleships began to enter service, and in 1898, she was transferred to the Northern Squadron, based in the English Channel.

[1][2] In the early 1870s, the Italian Regia Marina (Royal Navy) had begun its own expansion program under the direction of Benedetto Brin, which included the construction of several very large ironclad warships of the Duilio and Italia classes, armed with 450 mm (17.7 in) 100-ton guns.

The French initially viewed the ships as not worthy of concern, though by 1877, public pressure over the new Italian vessels prompted the Navy to order Amiral Duperré.

[4][5] Work on the design began with French Naval Minister Charles de Dompierre d'Hornoy's order for the Conseil des travaux to prepare two options for the new first-class ironclad on 20 October 1873.

The other, which carried all of its heavy guns in barbettes on the upper deck, went through a series of alterations and Sabattier eventually submitted it to Léon Martin Fourichon, who was then the naval minister, on 8 March 1876.

The Bayard and Vauban classes, intended for overseas deployments in the French colonial empire, were scaled down versions of Amiral Duperré.

Her hull featured a pronounced ram bow and had a short forecastle deck that extended from the stem to the forward main battery guns.

On her initial trials conducted in 1882, her engines reached a maximum of 7,357 ihp (5,486 kW) for a top speed of 14.3 knots (26.5 km/h; 16.5 mph).

[8][9] Amiral Duperré was designed with a three-masted schooner rig to supplement the steam engines,[5] though it was removed before she was completed.

For defense against torpedo boats, she carried twelve 37 mm (1.5 in) 1-pounder Hotchkiss revolver cannon, all in individual mounts.

Conway's All The World's Fighting Ships notes that "she was very vulnerable above [the waterline] and would not have stood much chance against HMS Inflexible.

She was placed in limited commission ten days earlier with a crew of 99 men to conduct her trials, which lasted through 20 November 1882.

The ship was placed in full commission on 17 April 1883, and five days later, she joined the Mediterranean Squadron, based in Toulon.

They fired at a range of 2,700 to 4,600 m (3,000 to 5,000 yd) and scored 22 percent hits with cast iron practice shells, though they conducted the test under unrealistic conditions, with Armide anchored in a calm sea.

[16] Another major set of exercises was held from 2 to 12 June at Ajaccio on the island of Corsica; Amiral Duperré and several other ironclads simulated a fleet attacking the port, which was defended by a coastal defense ship, three cruisers, and twenty torpedo boats.

During these exercises, the ironclads simulated an enemy fleet passing through the Strait of Gibraltar to attack the French Mediterranean coast; torpedo boats attempted to intercept them off Majorca.

From the year's maneuvers, the French concluded that the torpedo boats of the day were not sufficiently powerful enough to achieve any of the goals that had been assigned to them, particularly further from coast, but nevertheless still posed significant threats to blockading warships.

[18] At some point, one of the ship's main guns accidentally exploded, blowing its breech, though reports conflict over the timing and the results of the incident.

By the early 1880s, the French had developed more effective, slower-burning propellants, and had bored out the chambers of existing guns to accept larger charges of the new powder.

[20] Amiral Duperré took part in the 1889 fleet maneuvers in company with her division-mates and six other ironclads, along with numerous smaller craft.

The enemy squadron conducted a simulated attack on Toulon that night, but poor weather prevented further operations and the maneuvers were cancelled later on the 24th.

The exercises began four days later and concluded on 25 July, after which Amiral Duperré and the rest of the Mediterranean Fleet returned to Toulon.

[24] In late January 1895, Amiral Duperré and the protected cruiser Sfax took part in an experimental bombardment of a simulated coastal fortification on Levant Island.

The French determined that an excessive amount of ammunition was required to neutralize the guns, and had the fortification been returning fire, both ships likely would have been seriously damaged.

Amiral Duperré suffered an accidental explosion in one of her magazines on 13 May after the compartment became overheated from the adjacent boiler room.

[30] Later that year, she was transferred to the Northern Squadron in the English Channel, along with the two Amiral Baudins, Dévastation, Courbet, and Redoutable, since more modern pre-dreadnought battleships built in the mid-1890s had entered service by that time.

[33] While at sea for gunnery practice on 14 December, her starboard forward gun broke free in inclement weather and swung around, striking the bridge and causing significant damage to it and the fore mast.

[36] The work proceeded slowly, and as late as 1905, additional funds had been included in the year's budget to complete the installation of new boilers.