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.