Mikhail Gorbachev

1931 – 2022

Soviet reformer; glasnost and perestroika.

• 1985 CE

  Gorbachev

  Soviet reformer; glasnost and perestroika.

• 1986 CE

  Chernobyl disaster

  Reactor 4 at the Soviet Chernobyl nuclear plant explodes on April 26, releasing 400 times the radiation of the Hiroshima bomb. The disaster exposes Soviet secrecy, accelerates glasnost, and poisons public faith in nuclear power—reshaping global energy policy for decades.