The Saur Revolution or Sowr Revolution, also known as the April Revolution or the April Coup, was staged on 27–28 April 1978 by the People's Democratic Party of Afghanistan (PDPA) and overthrew Afghan president Mohammed Daoud Khan, who had himself taken power in the 1973 Afghan coup d'état and established an autocratic one-party system in the country. Daoud and most of his family were executed at the Arg in the capital city of Kabul by Khalqi military officers, after which his supporters were also purged and killed. The successful PDPA uprising resulted in the creation of a socialist Afghan government that was closely aligned with the Soviet Union, with Nur Muhammad Taraki serving as the PDPA's General Secretary of the Revolutionary Council. Saur or Sowr is the Dari-language name for the second month of the Solar Hijri calendar, during which the events took place.

The Military history of Afghanistan began before 1709 when the Hotaki dynasty was established in Kandahar followed by the Durrani Empire. The Afghan military was re-organized with assistance from the British in 1880, when the country was ruled by Amir Abdur Rahman Khan. It was modernized during King Amanullah Khan's rule in the early 20th century, and then during King Zahir Shah's forty-year rule; the Soviet Union supplied almost all weapons, training and military needs between the 1950s and 1970s. From 1978 to 1992, the Soviet-backed Afghan Armed Forces engaged in heavy fighting with the multi-national mujahideen groups who were then backed by the United States, Pakistan and others. After President Najibullah's resignation in 1992 and the end of Soviet support, the Afghan military dissolved into portions controlled by different factions. This era was followed by the Taliban regime, whose leaders were trained and influenced by the Pakistan Armed Forces.