Britain invaded Afghanistan after Amir Sher Ali Khan refused to allow a British diplomatic mission to enter the country. Afghanistan was an important frontier region for the British Raj as it bordered its imperial rival Russia which had made territorial gains in Central Asia.

Afghan prisoners of war held by the 45th Sikh Regiment of the Indian Army

Source: John Burke, Public domain, via Wikimedia Commons

The contest for influence in West and Central Asia between Russia and Britain is commonly referred to as the ‘Great Game’.