Cold War Timeline By arsnx.inc Jul 8, 1979 SALT II Mar 11, 1985 Mikhail Gorbachev Becomes Leader of the Soviet Union Dec 8, 1987 Intermediate-Range Nuclear Forces Treaty Signing Jun 4, 1989 Poland becomes independent Nov 9, 1989 Berlin Wall Torn Down Oct 3, 1990 Germany Reunited Dec 26, 1991 Soviet Union Dissolves