The South Manchuria Railway Company (Japanese: 満鉄); Mantetsu) was a company founded by Japan in 1906, after the Russo-Japanese War (1904-1905), and operated in Japanese-occupied Manchuria. From 1906 or 1910 until 1925, the company also operated the Koreanrailway system.
The company developed soy beans and mineral resources and brought them to Japan partly by its railway. It also built hotels, schools, libraries, etc., for Japanese immigrants. It closed by order of GHQ, and was taken over by the Soviet army in 1945.
Matsuoka gained international notoriety in 1933 when he announced Japan's departure from the League of Nations after the League’s criticism of Japan's operations in Manchuria, and led the Japanese delegation out of the League's assembly hall.
After leaving the foreign service, Matsuoka went to occupied Manchukuo and became President of the SouthManchurianRailroad, at which time he worked closely with Hideki Tojo (then serving as chief of the Kwantung Army's secret police).
Matsuoka became a fervent supporter of the idea of a Japanese attack on Russian lands, and constantly pressured Konoe and the leaders of the Imperial Japanese Army and Imperial Japanese Navy to mobilize the military for that purpose.