The war in Afghanistan began on 27 April 1978, when the People's Democratic Party of Afghanistan (PDPA) took power in a military coup, known as the Saur Revolution. Most of Afghanistan subsequently experienced uprisings against the PDPA government. The Soviet war in Afghanistan began in December 1979 to replace the existing communist government. Afghanistan's resistance forces, known as the mujahideen, fought against the Soviet invasion of Afghanistan. Some factions received support by the United States, with the Pakistani ISI serving as the U.S. middleman, and Saudi Arabia. The Soviet Union had to withdraw its troops in February 1989. The Soviet-backed Afghan communist government survived for three more years until the fall of Kabul in 1992.