Construction and early career

Osmaniye was ordered from the Robert Napier and Sons shipyard in Glasgow in 1862. Her keel was laid down in March 1863 and she was launched on 2 September 1864, originally under the name Gazi Osman. She began sea trials on 27 June 1865, by which time she had been renamed Osmaniye for Sultan Osman I, and she was commissioned into the Ottoman fleet in November that year.^[1][3] Early in the ship's career, the Ottoman ironclad fleet was activated every summer for short cruises from the Golden Horn to the Bosporus to ensure their propulsion systems were in operable condition.^[4]

The Ottoman fleet began mobilizing in September 1876 to prepare for a conflict with Russia, as tensions with the country had been growing for several years, an insurrection had begun in Ottoman Bosnia in mid-1875, and Serbia had declared war on the Ottoman Empire in July 1876. The Russo-Turkish War began on 24 April 1877 with a Russian declaration of war,^[5] but unlike many of the other, smaller Ottoman ironclads, Osmaniye and her sister ships remained in the Mediterranean Fleet.^[6] The Navy feared losing the largest ships of its fleet, and so kept them primarily in port for the duration of the conflict.^[7] The wooden warships of the Mediterranean Fleet sortied in April 1877 to patrol the coast of Albania, but Osmaniye and the rest of the ironclads remained in Souda Bay. In January 1878, as Russian forces approached the Ottoman capital through the Balkans, several vessels began transporting a reserve army from Dedeagac to Gelibolu; Osmaniye and the royal yacht Sultaniye joined the operation and carried the last elements of the army on 31 January.^[8]

1880s–1890s: inactivity and reconstruction

Osmaniye after her reconstruction

After the conclusion of the war in 1878, Osmaniye was laid up in Constantinople.^[2] The annual summer cruises to the Bosporus ended and the ships rarely left the Golden Horn. By 1883, the Ottoman ironclad fleet was in poor condition, and Osmaniye was unable to go to sea. Many of the ships' engines were unusable, having seized up from rust, and their hulls were badly fouled. The British naval attache to the Ottoman Empire at the time estimated that the Imperial Arsenal would take six months to get just five of the ironclads ready to go to sea. During this period, the ship's crew was limited to about one-third the normal figure.^[9]

In 1884, the 36-pounder guns were removed and a light battery of four 47 mm (1.9 in) quick-firing (QF) Hotchkiss guns and two 4-barreled 25.4 mm (1 in) Nordenfelt guns were added.^[2] In 1885–1886, the navy conducted experiments with converting Krupp breeck-loading fortress guns for use aboard Osmaniye. These were old guns manufactured in the mid-1870s, and the navy attempted to use the gun carriages from the existing muzzle-loading guns or the fortress mountings the Krupp guns had used ashore. After the work was completed in 1886, the ship briefly went to sea to test the guns, one of the only times the ship left the Golden Horn in the 1880s. During a period of tension with Greece in 1886, the fleet was brought to full crews and the ships were prepared to go to sea, but none actually left the Golden Horn, and they were quickly laid up again. By that time, most of the ships were capable of little more than 4 to 6 knots (7.4 to 11.1 km/h; 4.6 to 6.9 mph).^[10]

Osmaniye was again refitted at the Imperial Arsenal from 1890 to 1894, the first vessel to receive these updates. The ship's main battery was strengthened by the installation of two Krupp 240 mm (9.4 in) K L/35 guns. The upper deck was cut down forward and aft, where these guns were installed in individual barbettes. The barbettes, which appeared to be standard, heavily-armored mountings, actually consisted of about 250 mm (10 in) of wood and a thin 13 mm (0.5 in) plating. The guns themselves were fitted with 25 mm thick gun shields. Eight 150 mm (5.9 in) L/25 Krupp guns and six 105 mm (4.1 in) L/25 Krupp guns were installed on the broadside. The 150 mm guns took the place of the old Krupp guns in the gun battery, though half of the gun ports were plated over, while the 105 mm guns were installed in sponsons in the upper deck. Two of the 47 mm guns were removed and three more Nordenfelt guns were added. During the refit, she also received two vertical triple-expansion engines in place of her original machinery, and six coal-fired Scotch marine boilers replaced the box boilers; the new propulsion system allowed her to steam at a speed of 10 knots (19 km/h; 12 mph). She was again placed out of service in 1897 in Çanakkale.^[2][11]

Later career

That year, with the outbreak of the Greco-Turkish War in February 1897, Osmaniye was mobilized into the 1st Squadron. The Ottomans inspected the fleet and found that almost all of the vessels, including Osmaniye, to be completely unfit for combat against the Greek Navy, which possessed the three modern Hydra-class ironclads.^[12][13] Despite the fact that Osmaniye and her sisters had been refit just three years previously, the inspectors discovered that many of the pistons on their Krupp guns were bent, rendering the guns useless. Through April and May, the Ottoman fleet made several sorties into the Aegean Sea in an attempt to raise morale among the ships' crews, though the Ottomans had no intention of attacking Greek forces. On 15 May, Osmaniye took part in a training exercise that only served to highlight the poor training of the crews. With no possibility left to use the fleet in an active way, the Navy withdrew Osmaniye from service and removed her guns.^[14]

The condition of the Ottoman fleet could not be concealed from foreign observers, particularly the British Admiral Henry Wood and the German Admiral Eugen Kalau vom Hofe, who led the inspection. The fleet proved to be an embarrassment for the government and finally forced Sultan Abdul Hamid II to authorize a modernization program, which recommended that the ironclads be modernized in foreign shipyards. German firms, including Krupp, Schichau-Werke, and AG Vulcan, were to rebuild the ships, but after having surveyed the ships, withdrew from the project in December 1897 owing to the impracticality of modernizing the ships and the inability of the Ottoman government to pay for the work due to its weak finances. Following a lengthy process of negotiations, Krupp received the contract to rebuild Osmaniye on 11 August 1900, along with several other warships. By December 1902, however, Krupp withdrew from the deal, and Osmaniye was ultimately not reconstructed.^[15] In 1908, Osmaniye was towed back to Constantinople, where on 31 July 1909 she was decommissioned. She remained in the Navy's inventory until 1923, however, when she was sold to ship breakers.^[2]