Recent years have seen the re-emergence of the hardline Islamic Taliban movement as a fighting force in Afghanistan and a major threat to its government.
They are also threatening to destabilise Pakistan, where they control areas in the north-west and are blamed for a wave of suicide bombings and other attacks.
The Taliban emerged in the early 1990s in northern Pakistan following the withdrawal of Soviet troops from Afghanistan.
A predominantly Pashtun movement, the Taliban came to prominence in Afghanistan in the autumn of 1994.
It is commonly believed that they first appeared in religious seminaries - mostly paid for by money from Saudi Arabia - which preached a hard line form of Sunni Islam.
The Taliban's promise - in Pashtun areas straddling Pakistan and Afghanistan - was to restore peace and security and enforce their own austere version of Sharia, or Islamic law, once in power.
In both countries they introduced or supported Islamic punishments - such as public executions of convicted murderers and adulterers and amputations of those found guilty of theft.
Men were required to grow beards and women had to wear the all-covering burka.