Sultan Jan, also known as Sultan Ahmed Khan was installed as ruler of Herat

Herat

Herāt is the capital of Herat province in Afghanistan. It is the third largest city of Afghanistan, with a population of about 397,456 as of 2006. It is situated in the valley of the Hari River, which flows from the mountains of central Afghanistan to the Karakum Desert in Turkmenistan...

 (now in Afghanistan) by the Persians, as they evacuated Herat on March 4, 1857 in accordance with the Treaty of Paris

Treaty of Paris (1857)

The Treaty of Paris marked the end of the hostilities of the Anglo-Persian War. On the Persian side negotiations were handled by ambassador Ferukh Khan...

.

Sultan Jan captured Farah

Farah, Afghanistan

Farah is a city in western Afghanistan, situated at 650 m altitude, and located on the Farah River. It is the capital of Farah Province, and has a population of approximately 109,409....

 soon after, but it was recaptured by Dost Mohammad Khan

Dost Mohammad Khan

Dost Mohammad Khan was the Emir of Afghanistan between 1826 and 1863. He first ruled from 1826 to 1839 and then from 1843 to 1863. He was the 11th son of Sardar Pāyendah Khan who was killed by Zaman Shah Durrani in 1799...

, who then went on to lay siege to Herat. During the 10-month siege Sultan Jan died, and at the conclusion of the siege Herat returned to Afghan control.