Sir Dodmore Cotton (died 1628), was the first accredited British ambassador to the court of King Abbas I of Persia.
Dodmore Cotton was the third son of Sir Robert Cotton and Elizabeth, daughter of John Dormer. He matriculated from King's College, Cambridge in 1607, and that he was admitted to Lincoln's Inn Court in November 1608.
At court Dodmore obtained a position as a gentleman of the King's privy chamber, and so was well known to King Charles I when he was appointed ambassador to King Abbas I of Persia in 1627. He sailed in March in the Rose, an East Indiaman, for Gombrun (Bandar Abbas), in the Persian Gulf. He was accompanied by Thomas Herbert, Naqd Ali Beg (the former Persian ambassador to the Court of Saint James), and Sir Robert Shirley (an English advisor to Naqd Ali Beg).
During the voyage Beg who's ambassadorship in London had been a failure committed suicide. After touching at the Cape of Good Hope, Madagascar, and Swali in Surat, the three Englishmen arrived in Gombrun on 10 January 1628. Cotton, with Herbert and Shirley in his train, then proceeded to Ashraff, where he had an audience with King Abbas I. They then visited Mount Taurus and Casbin (Qazvin), where Shirley and Cotton died.