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The Japanese 5th Army, then known as the Yalu River Army, was initially raised on January 15, 1905, in the final stages of the Russo-Japanese War under the command of General Kawamura Kageaki out of only the 11th Infantry Division and three reserve brigades. It took successfully part in the battle of Mukden, when the 5th Army flanked the Russian left wing. It was disbanded at Mukden in January, 1906 after the signing of the Treaty of Portsmouth at the end of the war.
Second Sino-Japanese War and World War II
The Japanese 5th Army was raised again on December 7, 1937, in Manchukuo as a garrison force to guard the eastern borders against possible incursions by the SovietRed Army. As it was based on the eastern frontier, it was not a participant in the Nomonhan Incident, but was temporarily disbanded on February 26, 1938. It was re-established on May 19, 1939, under the direct control of the Imperial Japanese Army General Staff. It afterwards came under the command of the Japanese First Area Army, under the overall command of the Kwantung Army, and was used primarily as a training and garrison force. Its equipment and experienced troops were siphoned off to other commands in the southeast Asia theatre of operations as the war situation gradually deteriorated for Japan. By the time of the Soviet invasion of Manchuria, its poorly equipped and poorly trained forces were no longer a match for the experienced battle-hardened Soviet armored divisions, and it was driven back into defensive positions in Andong Province along the Korean border by the time of the surrender of Japan. It was formally disbanded at Jixi.
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