On 28 April 1978, a Marxist force led by Noor Mohammed Taraki deposed the Afghan president, Mohammed Daoud Khan. The Soviets supported Taraki as President Mohammed Daoud Khan had expelled 800 Soviet advisors from Afghanistan. However, growing popular resistance to the Soviet- backed regime led to a large-scale rebellion. Many Afghan army deserters joined the mujahedeen, the Muslim resistance forces. By mid-summer, the mujahedeen controlled 22 of Afghanistan's 28 provinces.
Hafizullah Amin, Premier of Afghanistan, deposed Taraki and became president on 18 September 1979. The Soviet Union did not approve of Amin's seizure of power and took steps to intervene in Afghanistan. On 25 December 1979, the Soviets invaded Afghanistan with three airborne divisions and four motorized rifle divisions. The Soviet invasion of Afghanistan led to nine years of destructive warfare with the mujahedeen. While the Soviets continued to pour troops into Afghanistan, shipments of American arms reached the mujahedeen through Pakistan.
In May 1988, the Soviet Union began to withdraw its forces from Afghanistan. The United Nations (UN) established the Good Offices Mission in Afghanistan and Pakistan (UNGOMAP). The mission was composed of experienced peacekeepers. Its objectives were to confirm the withdrawal of Soviet troops, help repatriate refugees, monitor the flow of arms into Afghanistan, and prevent any hostilities from developing between the Afghan and Pakistani governments. This small 50-man mission contained 5 veteran Canadian peacekeepers. Canada also contributed a number of sappers to assist mine education efforts in Afghan refugee camps in Pakistan.