After tension between Russia and Britain in Europe ended with the June 1878 Congress of Berlin, Russia turned its attention to Central Asia. That same summer, Russia sent an uninvited diplomatic mission to Kabul. Sher Ali Khan, the Amir of Afghanistan, tried unsuccessfully to keep them out. Russian envoys arrived in Kabul on 22 July 1878, and on 14 August, the British demanded that Sher Ali accept a British mission too.