Iwate (磐手) was the second and last Izumo-class armored cruiser (Sōkō jun'yōkan) built for the Imperial Japanese Navy (IJN) in the late 1890s.

Iwate played a minor role in World War I and began the first of her many training cruises for naval cadets in 1916, a task that would last until the end of 1939.

The 1896 Naval Expansion Plan was made after the First Sino-Japanese War and included four armored cruisers in addition to four more battleships, all of which had to be ordered from British shipyards as Japan lacked the capability to build them itself.

[1] Unlike most of their contemporaries which were designed for commerce raiding or to defend colonies and trade routes, Iwate and her half-sisters were intended as fleet scouts and to be employed in the battleline.

She carried up to 1,527 long tons (1,551 t) of coal[6] and could steam for 7,000 nautical miles (13,000 km; 8,100 mi) at a speed of 10 knots (19 km/h; 12 mph).

[4] The main armament for all of the "Six-Six Fleet" armored cruisers consisted of four 8-inch (203 mm) guns in twin-gun turrets fore and aft of the superstructure.

[13] At the start of the Russo-Japanese War, Iwate was the flagship of Rear Admiral Misu Sotarō, commander of the 2nd Division of the 2nd Fleet.

Tōgō chose to attack the Russian coastal defenses with his main armament and engage the ships with his secondary guns.

[15] Although many ships on both sides were hit, Russian casualties numbered some 150, while the Japanese suffered roughly 90 killed and wounded before Tōgō disengaged.

While scouting for Russian ships in the area, the Japanese cruisers bombarded the harbor and defenses of Vladivostok on 6 March to little effect.

The two units narrowly missed each other on the 24th in heavy fog and the Japanese proceeded to Vladivostok where they laid several minefields before arriving back at Wonsan on the 30th.

[18] The division failed to intercept the Russian squadron as it attacked several transports south of Okinoshima Island on 15 June due to heavy rain and fog.

The arrival of the Russians off Tokyo Bay on the 24th caused the Naval General Staff to order Kamimura to sail for Cape Toi Misaki, Kyūshū, fearing that Jessen would circumnavigate Japan to reach Port Arthur.

The General Staff finally ordered him back to Tsushima Island on the 30th; later that day he received word that Jessen's ships had passed through the Tsugaru Strait early that morning and reached Vladivostok on 1 August.

[19] On 10 August, the ships at Port Arthur attempted a breakout to Vladivostok, but were turned back in the Battle of the Yellow Sea.

36 miles (58 km) north of the island he encountered Kamimura's squadron, which consisted of four modern armored cruisers, Izumo, Tokiwa, Azuma, and Iwate.

[20] Jessen ordered his ships to turn to the northeast when he spotted the Japanese at 05:00 and they followed suit, albeit on a slightly converging course.

Jessen turned southeast in an attempt to open the range, but this blinded the Russian gunners with the rising sun and prevented any of their broadside guns from bearing on the Japanese.

At this time an eight-inch shell struck the roof of Iwate's starboard forward upper six-inch casemate and ignited the ready-use ammunition.

Kamimura circled Rurik to the south at 08:00 and allowed the other two Russian ships to get to his north and gave them an uncontested route to Vladivostok.

They fought a running battle with the Russians for the next hour and a half; scoring enough hits on them to force their speed down to 15 knots (28 km/h; 17 mph).

[22] About 10:00, Kamimura's gunnery officer erroneously informed him that Izumo had expended three-quarters of her ammunition and he turned back after a five-minute rapid-fire barrage.

[24] As the Russian 2nd and 3rd Pacific Squadrons approached Japan on 27 May, having sailed from the Baltic Sea, they were spotted by patrolling Japanese ships early that morning, but visibility was limited and radio reception poor.

After about half an hour, Admiral Ushakov was listing heavily enough that her guns could not elevate enough to bear and her commander ordered his crew to abandon ship and the scuttling charges detonated.

She began the first of her 16 training cruises on 20 April 1916, together with Azuma, and visited Australia and Southeast Asia before returning home on 22 August.

Iwate departed on 2 March 1918, bound for Central America, Hawaii and the South Sea Islands, and returned on 6 July.

The ships then visited Buenos Aires, Argentina and Durban, South Africa before heading home via the Indian Ocean, where they arrived on 8 February 1923.

[4] The ship continued to make training cruises, usually at two-year intervals, for the rest of the decade that took her to the East Coast of North America and the Mediterranean Sea among other places.

[40] On 19 March 1945, Iwate was attacked by American carrier aircraft, killing one crewman, although they failed to inflict any significant damage.

While not hit by any bombs, the three near misses sprang the ship's seams and the resulting flooding caused her to sink in shallow water at coordinates 34°14′N 132°30′E / 34.233°N 132.500°E / 34.233; 132.500 the following day.