I found about immigration of Belarusians in south America. Early immigrants from Grodnom governate began settling in Argentina. Those were farmers who were promised cheap , fertile land. Argentina was favourite destination until 1920s. In 30s Argentina has economic problems, so they restricted the number of immigrants. People began to apply for Parguay visas. The author states because western Belarusians were Polish citizens they were labeled as Poles in south america.

Those were economic immigrants (farmers) seeking land and better life. : http://www.nashapamiac.org/docs/Immigranty-chakarero.pdf