Soviet cosmonaut Sergei Krikaliov stayed in space during the collapse of the Soviet Union in 1991.
Unable to return home, he was forced to stay in space until further notice.
The cosmonaut finally returned to Earth on March 25, 1992, after 10 months in orbit, to a place that was very different from what it had been when he left. The Soviet Union had fractured in 15 nations, the presidents had changed and even his hometown, Leningrad, had returned to its former name: St. Petersburg.
Curiously, at that time, Krikaliov was supposed to serve in military reserves, and a desertion order was almost issued, before the army realized that its reserve soldier was not even on the planet. Krikaliov was called by many "the last citizen of the Soviet Union", so he left Earth as a citizen of the Soviet Union and landed as a citizen of the Russian Federation.
SOURCE: Internet