(b. 1793, Afghanistan--d. June 9, 1863, Herat), ruler of Afghanistan (1826-63) and founder of the Barakzay, who maintained Afghan independence during a time when the nation was a focus of political struggles between Great Britain and Russia.

Dost Mohammad was one of a number of sons of Payenda Khan, head of the Barakzay clan. In 1816 the clan rose in rebellion against the Afghan ruler Mahmud Shah, who had put to death his prime minister, a member of the clan. Following eight years of civil war, the clan claimed victory. Dost Mohammad emerged as its most powerful member, and he ascended the throne in 1826.

With Great Britain and Russia maneuverings for influence in Afghanistan, Dost Mohammad was forced to balance his nation between the two great powers. He also sought to recover territory lost from the central government's control during the civil war. The British, feeling that Dost Mohammad was either hostile to them or unable to resist Russian penetration, moved to take a direct role in Afghan affairs. First they negotiated unsatisfactorily with Dost Mohammad, and then they gave military support to an exiled Afghan ruler, Shah Shoja'. In 1839 they tried to use British troops to place Shoja' on the throne at the capital in Kabul; this action resulted in the First Anglo-Afghan War (1839-42). Dost Mohammad surrendered to British forces following the capture of his family in 1840.

The position of Shoja' and the British forces in Kabul, however, deteriorated rapidly. Shoja' was killed in a rebellion, and British troops were massacred as they attempted to retreat from the city. After the British departed in 1843, Dost Mohammad was restored to the throne. He then tried with some success to regain control of outlying sections of the country. He also reached an accommodation with the British, signing treaties of friendship in 1855 and 1857. In June 1863 his forces, under the command of his son-in-law, captured the city of Herat, and Dost Mohammad died there a few days later.