Japanese Naval Brigade (landing force) marching through Vladivostok, August 16, 1918 (Taisho 7) From "Zusetsu Showa no Rekishi. Vol.2"

Soon after the 1917 October Revolution in Russia (Taisho 6), the Soviets opted to unilaterally enter into talks with Germany. Apprehensive with the changed situation, the United Kingdom and France sought troops by from Japan and the United States to Siberia for the purpose among others, of occupying the Trans-Siberian Railway. The TERAUCHI Cabinet, however, was cautious about committing itself. On the other hand, Foreign Minister MOTONO Ichiro was a strong advocate of the Siberian venture.

This document is the Opinion Brief submitted by MOTONO to two Genro, YAMAGATA Aritomo and MATSUKATA Masayoshi, as well as to Prime Minister TERAUCHI Masatake, urging them to support the dispatch of Japanese troops to Siberia. Ultimately, however, the Brief failed to convince TERAUCHI and others to reverse their cautious stance, and MOTONO ended up resigning as Foreign Minister for reasons of health.

Once the United States, however, decided upon the policy of a joint Japanese-American deployment as a way to aid the Czechoslovakian military, Japan opted to send troops to Siberia.