Afghan diaspora or Afghan immigrants are citizens of Afghanistan who have emigrated to other countries and the people of Afghan origin who have been born outside Afghanistan. Traditionally the borders between Afghanistan and its neighboring states have been fluid and vague. Like many nations created by European Empires the borders often do not follow ethnic divisions and many ethnic groups and tribes present in Afghanistan are found on both sides of present day international borders. This meant that historically there has been much movement across present day barriers.
However since the Soviet invasion of Afghanistan refugees have fled into the surrounding states. After the Soviet pullout the ensuing internal civil war, Taliban conquest and most recently the Afghan war since 2001, have all meant a constant state warfare in Afghanistan. Millions have fled this periodically surging violence, with some returning in times of relative peace, only to flee again when renewed fighting breaks out. About six million Afghan refugees have fled to neighboring Pakistan and Iran, making Afghanistan the largest refugee-producing country in the world, a title it has held for 32 years. 95% of Afghan refugees are located in either Iran or Pakistan. Some NATO countries have also taken in Afghans that had worked with their respective forces in Afghanistan as refugees. Meanwhile, ethnic minorities of Afghan Sikhs and Hindus have often fled to India.
In 2013, more than 2.8 million Afghan refugees were living in Iran with only 0.8 million of them being registered as legal migrants and rest living as illegal refugees in Iran. Similarly 1.5 million officially registered Afghan refugees were reported to be living in Pakistan in addition to approximately one million more illegal refugees.
As shown in the table below, the refugees (both legal & illegal) have fled Afghanistan in four main waves: