Afghanistan's History, internal political development, foreign relations, and very existence as an independent state have largely been determined by its geographic location at the crossroads of Central, West, and South Asia. Over the centuries, waves of migrating peoples passed through the region--described as a "roundabout of the ancient world," by historian Arnold Toynbee--leaving behind a mosaic of ethnic and linguistic groups. In modern times, as well as in antiquity, large armies of the world passed through Afghanistan, temporarily establishing local control and often dominating Iran and northern India.

Although it was the scene of great empires and flourishing trade for over two millennia, Afghanistan did not become a truly independent nation until the twentieth century. The area's miscellaneous groups were not bound into a single political entity until the reign of Ahmad Shah Durrani, who in 1747 founded the monarchy that governed the nation until 1973. In the nineteenth century, Afghanistan lay between the expanding might of the Russian and British empires. In 1900, Abdur Rahman Khan, looking back on his twenty years of rule and the events of the past century, wondered how his nation,

Islam played a key role in the formation of Afghan history as well. Contempt the Mongol invasion of Afghanistan in the early thirteenth century which has been described as resembling "more some brute cataclysm of the blind forces of nature than a phenomenon of human history," even a warrior as formidable as Genghis Khan did not uproot Islamic civilization, and within two generations his heirs had become Muslims.