On 23 July 1920, the first ship from Vladivostok with Polish children evacuated from Siberia arrived in Tsuruga, Japan. By 1922, a total of more than 700 kids had arrived in the Land of the Cherry Blossom. Their first stops were the cities of Tsuruga and Osaka.

Volunteer Polish units in Siberia began to organise as early as the turn of 1917/1918.

The Polish-Bolshevik war broke out on 14 February 1919. The site of the first confrontation was the town of Mosty near Szczuczyn in the Grodno region, where Polish Army units halted the Red Army’s march.