Envoy
In the Peshwa court he obtained his first opportunity of distinction, being attached in the capacity of diplomatist to the mission of Sir Arthur Wellesley to the Marathas. When, on the failure of negotiations, war broke out, Elphinstone, though a civilian, acted as virtual aide-de-camp to Wellesley. At the Battle of Assaye, and throughout the campaign, he displayed rare courage and knowledge of tactics such that Wellesley told him he ought to have been a soldier. In 1804, when the war ended, Elphinstone was appointed British resident at Nagpur. This gave him plenty of leisure time, which he spent in reading and study. Later, in 1807, he completed a short stint at Gwalior.
In 1808 he was appointed the first British envoy to the court of Kabul, Afghanistan with the object of securing a friendly alliance with the Afghans against Napoleon's planned advance on India. However this proved of little value, because Shah Shuja was driven from the throne by his brother before it could be ratified. The most valuable permanent result of the embassy was in Elphinstone's work titled Account of the Kingdom of Cabul and its Dependencies in Persia and India (1815).
After spending about a year in Calcutta arranging the report of his mission, Elphinstone was appointed in 1811 to the important and difficult post of resident at Pune (formerly known as Poona). The difficulty arose from the general complication of Maratha politics, and especially from the weakness of the Peshwas, which Elphinstone rightly read from the first. The tenuous peace between the Peshwas was broken in 1817 with the Marathas declaring war on the British. Elphinstone assumed command of the military during an important crisis during the Battle of Khadki and managed to secure a victory despite his non-military background. As reparations, Peshwa territories were annexed by the British. Elphinstone became the Commissioner of the Deccan in 1818.
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