Later they returned to Estonia and became Estonian citizens. This is where Schmidt began his international chess career which lasted from 1935 until 1950.
In 1939 they were expelled from Estonia and were again given German citizenhsip. During World War 2, Schmidt was one of the best players in the world with a rating over 2600.
In 1952 he emigrated to the U.S.A., with his family, and focussed on his scientific career. The family finally acquired U.S. citizenship in 1957.
This book contains all of his games that i have been able to find, many with his own notes.