South Manchuria Railway Co. (南満州鉄道株式会社; 1906 - 1945)

South Manchuria Railway Co. (南満州鉄道株式会社; 1906 - 1945) was a conglomerate initially formed to manage the southern section of the China Eastern Railway, won from Russia in the Treaty of Portsmouth after the Russo-Japanese War. In time, Mantetsu would move into a wide range of industries including shipping, hotels, mining, and publishing, and become the largest company by value in Japan, constituting a significant portion of the Japanese economy in itself. Mantetsu was the primary means by which Japan colonized Manchuria, a process well-underway before the establishment of Manchukuo in 1932. Its publications, often in conjunction with Mantetsu's various 'investigation' bureaus, generally dealt with the economy, infrastructure, and society of Manchuria and northern China but later expanded to cover all of China and beyond, in effect serving as an intelligence wing of the Japanese government and military.