English poet, translator, and diplomat whose version of Camões' Os Lusíadas is a major achievement of English verse translation.

Educated at Cambridge, he was appointed secretary to the English embassy at Madrid in 1635. At the outbreak of the Civil War he joined the King. In 1648 he became treasurer to the navy, and in 1650 he was dispatched by Charles II to obtain help from Spain. Although this was refused, Fanshawe was created a baronet; he rejoined Charles in Scotland and was taken prisoner at the Battle of Worcester. On Cromwell's death he reentered the King's service in Paris and after the Restoration was appointed ambassador to Portugal and later to Spain.

Fanshawe's Il Pastor Fido, The faithful Shepherd, a translation of Battista Guarini's Il Pastor Fido, was published in 1647. A second edition “with divers other poems” (1648) included his version of the fourth book of Virgil's Aeneid, in Spenserian stanza. His Selected Parts of Horace appeared in 1652. The great work of his retirement during the Protectorate was his translation in the original metre of the Os Lusíadas of Camões (1655).