a republic in central Asia: became independent in 1919; occupied by Soviet troops, 1979–89; controlled by mujaheddin forces from 1992 until 1996 when Taliban forces seized power; in the US-led 'war on terror' (2001) the Taliban were overthrown although their insurgency continues; generally arid and mountainous, with the Hindu Kush range rising over 7500 m (25 000 ft) and fertile valleys of the Amu Darya, Helmand, and Kabul Rivers. Official languages: Pashto and Dari (Persian), Uzbek and Turkmen also widely spoken. Religion: Muslim. Currency: afghani. Capital: Kabul. Pop: 35 530 081 (2017 est). Area: 657 500 sq km (250 000 sq miles)