Complex sentence: In Manchu in 1920 Japan defeated and pushed back Russia far inland, then in 1921, in a deal to avoid further attacks from Japan, Russia executed all of the Korean freedom fighters that were living in modern-day Svobodny, Russia.
Split into simpler sentences: In Manchu in 1920, Japan defeated and pushed back Russia far inland. Then in 1921, in a deal to avoid further attacks from Japan, Russia executed all Korean freedom fighters living in modern-day Svobodny, Russia.