The Ildertons of Ilderton, established in Northumberland since the twelfth century, failed in the male line two centuries later but their surname was perpetuated when a Yorkshire landowner, Thomas Wetewang, took the Ilderton name after his marriage to Alice, the heiress of Henry de Ilderton (fl.1328). In the second half of the fourteenth century this new incarnation of the Ildertons prospered. Sir Thomas Ilderton† had a long military career in France and Scotland, and held important military office on the borders: in July 1377 he was appointed as chancellor and chamberlain of Berwick-upon-Tweed under Henry Percy, earl of Northumberland, the warden of the marches, and in April 1380 John of Gaunt, duke of Lancaster, named him as constable of the great castle of Dunstanborough. Thereafter he served both these lords, even after enmity grew between them in the 1380s. Our MP’s father, Edward, was probably Sir Thomas’s son. He too was employed on the Scottish borders, but appears to have died around 1404.
Ilderton was to have a much less significant career than that of his putative grandfather. A minor at his father’s death, nothing is known of his minority. He was of age by 23 May 1420 when he headed a jury at an inquisition post mortem held at Newcastle-upon-Tyne. Given his youth and relative poverty (he was assessed on an income of only £13 p.a. in the subsidy returns of 1436), it is very surprising that he should then have been elected to represent his native county in the successive Parliaments of 1423 and 1425. On both occasions he was elected alongside men in the service of Thomas Langley, bishop of Durham, the chancellor at the time of the first Parliament: in 1423 his fellow MP was the bishop’s steward, Thomas Holden*, and in 1425 it was another of Langley’s leading servants, Sir Robert Ogle I*.
These two elections to Parliament show that Ilderton was a man of some significance, as does his marriage to a daughter of the important Westmorland family of Musgrave. In March 1435 Langley issued a licence for the Clifford land in Grindon, near Norham, to be settled on feoffees to the use of the couple.
During this period nothing is known of the former MP beyond the fact that he was still alive. It may be that he was plagued by debilitating ill-health, but, if so, he survived until 27 June 1467 when a writ of diem clausit extremum was issued. By then Sir Thomas was also dead (perhaps falling in the Percy ranks at the battle of Towton), and, although the details are obscure, there followed a dispute between Sir Thomas’s widow and their two daughters, on the one hand, and our MP’s heir-male, his nephew, yet another Thomas. By 1478 the manor of Ilderton was in the nephew’s hands.