After the World War II, Riewe was taken in the custody by the Soviet Union, and held in Russia to work on their nuclear weapons but went onto a strike at a defense facility in 1948 where he was accused of sabotage.

Karl-Heinrich Riewe was born in Frankfurt, Hesse, Germany, on June 26, 1907, into a German Jewish family.

: 363 [2] He struggled to find employment in Germany and submitted an application for a teaching position in the Wesleyan University in the United States.

: 121 [1] In June 1941, Riewe co-authored a paper electron optics and plasma physics with the nuclear physicist Fritz Houtermans.

: 5–6 [4] Eventually, Riewe was taken into the Soviet custody and was sent to Russia to work on the Soviet nuclear weapons program at the Laboratory V run by Heinz Pose in Obninsk, either in the initial sweep by the special search teams or later by Pose's six-month recruitment trip, from March to August 1946, with NKVD General Kravchenko and two other officers.

[5][6] In 1948, Riewe and fellow scientist, Dr. Renger, went on strike for reasons of their work conditions or hoping to be sent back to Germany after their two-year contracts expired.