Thomas Cokayn was a Cornishman by birth and probably came from either Lostwithiel or one or other of the parishes of Morval and St. Martins’ near Looe, all three being places which he mentioned in his will. He may well have been a descendant of Henry Cokayn, feodary of the duchy of Cornwall from 1369 to 1371, who had lived at Lostwithiel.
Sir John Herle
†, who named him as a feoffee of his manor of Tywardreath, near Lostwithiel. From 1423 onwards he acted as a trustee of the estates in Cornwall, Devon, Somerset and Oxfordshire belonging to the Peverell sisters and their husbands, Sir William Talbot and Sir Walter Hungerford, continuing to serve in this capacity for several years after Hungerford had been appointed treasurer of England.
John
†. In about 1430, however, he decided to make London his main place of residence. It had been there that, in 1428, he had been chosen, along with John Hody, the future chief justice, to arbitrate in a dispute over property; and in 1432 he became a member of Lincolns Inn. Here he spent the Christmas vacation of 1432-3, and shortly afterwards he was asked by a fellow member, Andrew Sperlyng, to be a feoffee of his manor in Long Crendon, Buckinghamshire. Although in 1434 Cokayn served as one of the quorum on a royal commission sent to investigate a crime committed at Plymouth, all of his other public duties were concerned with matters affecting London: problems of drainage, the blockage of water-courses and extortionate prices for grinding corn. Similarly, his clientele now came to be drawn from among landowners living near the capital: for instance, from 1433 he acted as a feoffee of the manor of Batchworth in Rickmansworth.
It is possible that Cokayn married into a London mercer’s family. Certainly, he established several close contacts with members of the powerful Mercers’ Company: in 1430 and 1432, on four different occasions, he stood surety at the Exchequer for John Pidmyll when the latter took on the farm of the much-disputed Hertfordshire manor of ‘Maudeleyns’; and he was to choose as an executor of his will a former master of the Company,
Henry Frowyk
†.
