He hired a mercenary army of Ghalcha highlanders, and conquered the western half of the Fergana Valley, including Khujand and Tashkent.

In 1841, the British officer Captain Arthur Conolly failed to persuade the various khanates to put aside their differences, in an attempt to counter the growing penetration of the Russian Empire into the area.

[6][4][page needed] Following this, Madali Khan, who had received Conolly in Kokand, and who had also sought an alliance with Russia, lost the trust of Nasrullah.

The Emir, encouraged by the conspiratorial efforts of several influential figures in Kokand (including the commander in chief of its army), invaded the Khanate in 1842.

When Alimqul was killed in 1865 during the battle with Russia for Tashkent, many Kokandian soldiers fled to join Yaqub Beg, helping him establish his dominion (known as Yettishar) throughout the Tarim Basin, which lasted until 1877, when Qing reconquered the region.

He was succeeded by his son, Nasruddin Khan, whose anti-Russian stance provoked the annexation of Kokand[9] by generals Konstantin von Kaufman and Mikhail Skobelev.