On June 12, 1979, Soviet forces began a full-scale invasion of Afghanistan in support of the communist government, marking the start of a nine-year conflict. The war became a key Cold War battleground, with the U.S. and its allies providing support to Afghan resistance fighters. The Soviet forces faced fierce opposition from Afghan guerilla fighters, and the war caused significant casualties on both sides. The Soviet Unions eventual withdrawal in 1989 was a significant defeat for the USSR. The war had lasting consequences for Afghanistan, contributing to years of instability and violence in the region.