John Conduitt (/ˈkɒndwɪt, -duːɪt, -djuːɪt/; c. 8 March 1688 – 23 May 1737) was a British Member of Parliament and Master of the Mint who married Sir Isaac Newton's niece.
Conduitt was the son of Leonard and Sarah Conduitt, and was baptized at St Paul's, Covent Garden, London, on 8 March 1688. He was admitted to St Peter's College, Westminster School, as a King's scholar in June 1701. In 1705, while at Westminster, he was elected a Queen's scholar to Trinity College, Cambridge, with three others He was admitted there in June of that year and matriculated to the University, but did not graduate, staying only two years.
By 1707, based on his own account he was "travelling" in Holland and Germany. In September 1710, he became judge advocate with the British forces in Portugal. He was a "very pretty gentleman" according to James Brydges. From October 1710, he acted as the Earl of Portmore's secretary when the latter arrived in Portugal (N&Q). During this time, he kept the Earl of Dartmouth informed as to the Portuguese court. He returned to London by October 1711 with Lord Portmore. During the following year, he was made a captain in a regiment of the dragoons serving in Portugal, but by September 1713 he had been appointed Deputy Paymaster General to the British forces in Gibraltar. The posts appear to have been remunerative, and in May 1717 he returned home to England a richer man.