Lematon was one of at least five sons of the minor Northumberland landowner, John Barker, who took their name from the small hamlet of Lemington in the parish of Edlingham. Little is known of Lematon’s father, but his identity is confirmed in a deed of November 1449 when on the death of his elder brother John the family estates were conveyed to Richard.
By the mid 1440s Lematon had returned to England and settled in York, where he was elected to a first civic office in February 1446 as one of the city chamberlains, serving a term which saw the construction of a new common hall.
By the beginning of the 1450s Lematon was himself a prominent and wealthy merchant. Little evidence survives of the scale of his dealings in wool, but in 1452-3 he was importing quantities of woad and canvas into Kingston-upon-Hull.
In parallel with his wealth, Lematon’s standing in the city of York proceeded to grow. In 1451 he and his wife were admitted to the prestigious guild of Corpus Christi.
Scant evidence survives of the remainder of Lematon’s career. He is known to have engaged in domestic trade in partnership with his earlier associate Stocton in the early 1460s, when an obligation made by them jointly to the mayor and commonalty of Carlisle became the subject of a dispute between the citizens and a former mayor.
