William Coryton (1580 – 1651) was an English politician who sat in the House of Commons at various times between 1624 and 1641. He was expelled from parliament for falsyfying returns.
Coryton was the eldest son of Peter Coryton of Coryton and Newton Ferrers, Devon, and his wife Joan Wreye, daughter of John Wreye of Militon, Cornwall.
Coryton was appointed vice-warden of the stannaries in 1603 and High Sheriff of Cornwall for 1613. In 1624 he was elected Member of Parliament for Cornwall. He was elected MP for Liskeard in 1625 and again MP for Cornwall in 1626.
In July 1627 Coryton was arrested for refusing to subscribe the forced loan of that year, and imprisoned in the Fleet prison, where he remained until March 1628. His place of vice-warden of the stannaries was in the meantime given to John Mohun. In view of the opening of parliament in 1628, he was released and was re-elected MP for Cornwall. He spoke in the debate on religious grievances on 27 January 1629, in that on tonnage and poundage which followed, and in other debates. His tone was described as "studiously moderate".
Coryton was present on 2 March 1629 when the speaker was forcibly held in his seat. After his fellow MP Sir John Eliot had read a remonstrance on tonnage and poundage, the speaker Sir John Finch refused to put it to the house, and rose to dissolve the assembly. Finch was then held in his seat by Denzil Holles and Benjamin Valentine while resolutions against Arminianism and illegal exactions were read and declared carried. Coryton was subsequently charged with having aided and abetted Eliot, Holles, and the rest, and even with having assaulted Francis Winterton, member for Dunwich, Suffolk. He was summoned with the other "conspirators" before the Star-chamber, and appeared, but refused to plead on the ground of privilege of parliament. He was accordingly committed a close prisoner to the Tower of London. An application for a habeas corpus made on his behalf in the following May was refused. He made submission, however, was released, and reinstated in his office in the stannaries court at some date prior to 16 January 1630. His administration of justice in the stannaries court gave much dissatisfaction to suitors, and in or about 1637 he was arrested on a charge of false imprisonment. The matter, however, was not pressed, and on his release he resumed his judicial duties.
In April 1640 Coryton was elected MP for Grampound for the Short Parliament in an apparent double return, and was re-elected MP for Grampound for the Long parliament in November 1640. He was at the time mayor of Bossiney and was found guilty on petition of falsifying the returns for the election at Bossiney. He was also found guilty of maladministration in the stannaries court and was "not admitted to sit" in parliament. At the same time he was removed from the office of vice-warden of the stannaries, and also from the stewardship of the duchy and deputy-lieutenancy of the county of Cornwall which he then held.
Coryton died on 1 May 1651, and was buried in the church of St Mellion, near Plymouth. A rhyming inscription on his tomb describes him as
Both good and great, and yet beloved;
In judgment just, in trusts approved.
Coryton married Elizabeth Chichester, daughter of Sir John Chichester de Raleigh, who survived him, dying on 26 January 1656–7, and had four sons and seven daughters. His son and successor, John, was created a baronet on 27 February 1662 (see Coryton baronets).