Sir John III Speke (1442–1518) of Whitelackington, Somerset and of Heywood in the parish of Wembworthy and of Bramford Speke both in Devon, was Sheriff of Devon in 1517 and a Member of Parliament (1477). He was knighted in 1501. His monument is the Speke Chantry in Exeter Cathedral in which survives his recumbent effigy.