The Dupleix class consisted of three armored cruisers built for the French Navy () at the beginning of the 20th century. Designed for overseas service and armed with eight guns, the three ships of the class were smaller and less powerfully armed than their predecessors.
was initially assigned to the Atlantic Division () as its flagship. Her sister ships were initially assigned to the Mediterranean Squadron (), although relieved Dupleix as flagship of the Atlantic Division in 1905. Dupleix was reduced to reserve from 1906 to 1909 before she was sent to the Far East in 1910 as the flagship of the ships there. Desaix and exchanged assignments in 1907, although the former ship returned to the Atlantic in 1908 before being placed in reserve from 1909 to 1914. Kléber was also placed in reserve in 1909, but she was reactivated two years later to join Dupleix in the Far East before returning home in 1913 to be placed in reserve again.
As tensions rose shortly before the beginning of World War I in August 1914, both Desaix and Kléber were reactivated. When the war began they were assigned to defend Allied shipping in the English Channel and intercept German ships attempting to pass through. At that time, Dupleix was still in the Far East. Before she was transferred to the Eastern Mediterranean in May 1915, the ship spent most of her time on escort duty in the Indian Ocean and Red Sea. Joined by Kléber that same month, they were two of the ships tasked to blockade the Aegean coast of Ottoman Turkey. Desaix was the first of the sisters to be transferred to the Mediterranean in February 1915 and spent the next year patrolling off the coast of the Ottoman Levant and in the central Mediterranean.
To help protect Allied shipping from German commerce raiders, the sisters were transferred to French West Africa for convoy escort duties in mid-1916 and remained there for the next year. Personnel shortages caused Kléber to be ordered home in mid-1917, but she struck a naval mine laid by a German submarine in June and sank; most of her crew was rescued by ships in the area. Dupleix followed her home in October and was placed in reserve. Desaix remained in West Africa for the rest of the war.
Dupleix was decommissioned in 1919 and Desaix was transferred to the Far East that same year. After the latter's return in 1921, she was also decommissioned. Dupleix was sold for scrap in 1922 and Desaix followed five years later.
Background French cruiser policy during the decade from the mid-1880s was incoherent as three different factions of the navy fought amongst themselves in four forums, the Navy Ministry (), the Budgetary Committee of the Chamber of Deputies (), the Supreme Naval Council () that proposed shipbuilding programs and ship characteristics to the Navy Minister, and the Board of Construction () that was responsible for evaluating ship designs. The partisans of the (Young School) wanted fast, lightly armed ships for commerce raiding, the traditionalists who wanted cruisers to defend the colonies and the modernists that desired armored cruisers and small scout cruisers to operate with the battle fleet.Jordan & Caresse, p. 77; Ropp, p. 284
A traditionalist Navy Minister, Vice Admiral () Armand Besnard, succeeded the liberal politician Édouard Lockroy in April 1896, after the latter had authorized construction of the very large armored cruiser in the 1896 budget proposal, despite opposition from the . After rejecting a repeat protected cruiser like in the 1896 budget, Lockroy and his allies in the Budget Committee were willing to accept smaller cruisers in the following year's budget. The rejected Besnard's proposal for a protected cruiser in late 1896, saying that the navy "needed ships that can deal out and withstand punishment",Jordan & Caresse, p. 77 but Besnard authorized construction of a few weeks later in the 1897 budget proposal anyway.Ropp, p. 286
In the meantime, the Superior Naval Council had produced a new naval program that included an additional three each armored and protected cruisers for overseas service and five armored cruisers for service with the battle fleet. For the 1898 budget, Besnard proposed one battleship, two armored cruisers and two protected cruisers, but Lockroy and his allies, probably influenced by the ideas of Vice Admiral François Ernest Fournier, who believed that most cruiser tasks, including commerce raiding, would be better performed by armored cruisers smaller than Jeanne d'Arc, deleted the battleship and offered him 120 million francs for armored cruisers. Besnard initially proposed adding an enlarged version of Jeanne d'Arc, but this was rejected by the in early 1897. He countered with a revised program of three armored cruisers for overseas duties, which became the Dupleix class, and three armored cruisers for the fleet. This satisfied the Superior Naval Council's objectives and all three factions as Fourier's ideas showed that armored cruisers could accomplish the 's preferred strategy of commerce raiding. It also neatly consumed the Budget Committee's 120 million francs as each of the Dupleixs cost about 19 million francs and the Gueydons 21 million francs.Jordan & Caresse, pp. 77–78; Ropp, pp. 286, 288
Preliminary design work in December 1896 was for a ship armed with ten guns, two in single-gun turrets fore and aft of the superstructure and the remaining eight in casemates, protected by a waterline armor belt. The thought that the belt protection was too weak and that the ships needed more endurance. The naval architect Louis-Émile Bertin, recently appointed as the Director of Naval Construction (), agreed and revised the design, sacrificing one pair of guns for more armor and additional coal, which increased its displacement. The accepted his revised design on 4 May 1897, although complaining about the deleted guns.Jordan & Caresse, pp. 79–80
Dupleix was ordered from one of the naval dockyards on 18 December and orders for the other two followed on 28 December. Six months later, the proposed revising the armament, exchanging the single-gun turrets and the casemated guns for four twin-gun turrets, two replacing the turrets on the centerline and two wing turrets, one on each broadside, and adding four guns in casemates. By this time, preliminary work had already begun on Dupleix and Lockroy, recently returned to office, suggested suspending work on the ships while studies were done. Bertin opposed the changes, but produced drawings by early March 1899, despite the work load on his designers who were focused on other projects, and they were approved by the Minister on 6 April. The changes greatly retarded the progress on the two ships ordered from private dockyards, which had already been laid down in early 1899.Jordan & Caresse, pp. 81–82
Design and description The Dupleix-class ships were much smaller and more lightly armed than Jeanne d'Arc. They measured long overallSilverstone, p. 79 with a beam of and had a maximum draft of . The cruisers displaced as designed. To reduce biofouling, their hulls were sheathed in teak. The ships normally had a crew of 19 officers and 550 enlisted men, but accommodated 24 officers and 583 enlisted men when serving as flagships.Jordan & Caresse, pp. 82, 91
The ships' propulsion machinery consisted of three vertical triple-expansion steam engines, each driving a single propeller shaft, using steam provided by water-tube boilers, but the types of machinery differed between them. The first two ships, and , had four-cylinder engines fed by 24 Belleville boilers with a working pressure of while the last ship, , had three-cylinder engines that used 20 Niclausse boilers at . The engines of all three ships were designed to produce a total of that was intended to give them a maximum speed of . Despite exceeding their horsepower rating, only Kléber met or exceeded her designed speed during their sea trials, the ships attaining from . The sisters carried up to of coal and could steam for at a speed of .Jordan & Caresse, pp. 82, 94
Armament The ships of the Dupleix class had a main armament that consisted of eight quick-firing (QF) 45-caliber Canon de 164 mm Modèle 1893–96 guns. They were mounted in four twin-gun turrets, one each fore and aft of the superstructure and a pair of wing turrets amidships.Chesneau & Kolesnik, p. 305 The guns fired shells at muzzle velocities ranging from . This gave them a range of about at the turrets' maximum elevation of +15 degrees. Each gun was provided with 200 rounds, of which 44 shells were stowed in the turrets, which it could fire at a rate of three rounds per minute.Friedman, p. 223; Jordan & Caresse, pp. 85, 87, 89
The cruisers' secondary armament consisted of four 45-caliber QF Canon de 100 mm Modèle de 1893 guns on single mounts in unprotected casemates in the hull. Their shells were fired at muzzle velocities of at a rate of six rounds per minute. At their maximum elevation of +20 degrees, the guns had a range of . The sisters carried 250 rounds for each gun. For defense against torpedo boats, they carried ten and four Hotchkiss guns, all of which were on single mounts.Friedman, pp. 226–227; Jordan & Caresse, pp. 82, 89–90 The ship were also equipped with two above-water torpedo tubes, one on each broadside.
Protection The nickel steel armor belt of the Dupleix-class cruisers extended from below the waterline to above itJordan & Caresse, p. 91 and covered the entire length of the ship except for of the stern where it ended in a transverse bulkhead thick. The armor was thick, although it reduced to 84 mm in front of the forward turret and thinned to at its lower edge.Jordan & Caresse, pp. 91–92
The curved protective deck had a total thickness of on the flat and on the upper part of the curved portion where it met the bottom edge of the belt armor. Behind the belt armor was a highly subdivided watertight internal cofferdam. The face and sides of the gun turrets were protected by Harvey face-hardened armor plates, although their roofs were only thick. The armor plates of the gun barbettes was thick. The sides of the elliptical conning tower were 100 to 120 millimeters thick.Jordan & Caresse, p. 92
Ships + Construction dataNameBuilderLaid downJordan & Caresse, p. 81LaunchedCommissioned FateJordan & Caresse, pp. 245–256, 256Arsenal de Rochefort 18 January 1899 28 April 1900 15 September 1903 Sold for scrap, 1922Ateliers et Chantiers de la Loire, NantesEarly 1899 21 March 1901 5 April 1904 Sold for scrap, 1927Forges et Chantiers de la Gironde, Bordeaux 20 September 1902 4 July 1904 Sunk by a mine, 27 June 1917
Service history The first ship completed, Dupleix, was initially assigned to the Atlantic Division as its flagship. Her sisters were initially assigned to the Mediterranean Squadron's Light Squadron (), although Desaix relieved Dupleix as flagship of the Atlantic Division in 1905. In her turn Kléber relieved Desaix as flagship of the Atlantic Division in 1907. Desaix took Klébers place in the Light Squadron. While visiting the United States later that year, the cruiser accidentally collided with and sank an American cargo ship and participated in the Jamestown Exposition, celebrating the tercentenary of the founding of Jamestown, Virginia. At the beginning of 1908, Kléber became flagship of the Moroccan Division ().Jordan & Caresse, pp. 95, 210; Sieche, pp. 150, 155, 157
The sisters all spent significant amounts of time before 1914 in reserve. Dupleix from 1906 to 1909, Desaix from 1909 to 1914 and Kléber in 1909–1910 and 1913–1914. Dupleix was reactivated in 1910 to serve as the flagship of the Far Eastern Division () and was joined by Kléber in 1911–1912. Dupleix was replaced as flagship in 1913 by the larger and more spacious, albeit older, armored cruiser .Jordan & Caresse, p. 95
World War I