Shortly after the September 11 attacks, the United States declared the war on terror and subsequently led a multinational invasion of Taliban-ruled Afghanistan. The stated goal was to dismantle al-Qaeda, which had executed the attacks under the leadership of Osama bin Laden, and to deny Islamist militants a safe base of operations in Afghanistan by toppling the Taliban government. The United Kingdom was a key ally of the United States, offering support for military action from the start of the invasion preparations. The American military presence in Afghanistan greatly bolstered the Northern Alliance, which had been locked in a losing fight with the Taliban during the Afghan Civil War. Prior to the beginning of the United States' war effort, the Taliban had seized around 85% of Afghanistan's territory as well as the capital city of Kabul, effectively confining the Northern Alliance to Badakhshan Province and smaller surrounding areas. The American-led invasion on October 7, 2001, marked the first phase of what would become the 20-year-long War in Afghanistan.

The Islamic Emirate of Afghanistan, also referred to as the First Islamic Emirate of Afghanistan, was a totalitarian Islamic state led by the Taliban that ruled most of Afghanistan from 1996 to 2001. At its peak, the Taliban government controlled approximately 90% of the country, while remaining regions in the northeast were held by the Northern Alliance, which maintained broad international recognition as a continuation of the Islamic State of Afghanistan.