PITT, THOMAS (1653–1726), British East India merchant and politician, usually called “Diamond Pitt,” was born at Blandford, Dorset, on the 5th of July 1653. In early life he went to India, and from his headquarters at Balasore he made trading journeys into Persia and soon became prominent among those who were carrying on business in opposition to the East India Company. Twice he was arrested by order of the company, the second time being when he reached London in 1683, but after litigation had detained him for some years in England he returned to India and to his former career. Unable to check him the East India Company took him into its service in 1695, and in 1697 he became president of Fort St George, or Madras. Pitt was now very zealous in defending the interests of his employers against the new East India Company, and in protecting their settlements from the attacks of the natives; in directing the commercial undertakings of the company he also appears to have been very successful. Soon, however, he had a serious quarrel with William Fraser, a member of his council, and consequently he was relieved of his office in 1709, although he was afterwards consulted by the company on matters of importance. During his residence in India Pitt bought for about £20,000 the fine diamond which was named after him; in 1717 he sold this to the regent of France, Philip duke of Orleans, for £80,000 or, according to another account, for £135,000. It is now the property of the French government. During his former stay in England Pitt had bought a good deal of property, including the manor of Old Sarum, and for a short time he had represented this borough in parliament. After his final return from India in 1710 he added to his properties and again became member of parliament for Old Sarum. He died at Swallowfield near Reading on the 28th of April 1726. His eldest son, Robert, was the father of William Pitt, earl of Chatham (q.v.), and of Thomas Pitt (d.1761), whose son became the first Lord Camelford; his second son, Thomas Pitt (c. 1688–1729), having married Frances (d. 1772), daughter of Robert Ridgeway, 4th earl of Londonderry (d. 1714), was himself created earl of Londonderry in 1726.