The family of Yerburgh had been established at Yarburgh near Louth since the time of the Norman Conquest. Its antiquity did not bring it any great distinction, although it did play a modest part in public affairs. Sir John Yerburgh† represented Lincolnshire in the Parliament of 1325 and another John† represented Grimsby in that of January 1339. Later in the century a third John was clerk of the wardrobe to the duke of Lancaster, and early in the next yet another John was one of the clerks of the court of common pleas. The latter founded a junior branch of the family settled at Reepham near Lincoln.
Yerburgh’s father, assessed on an income of £20 p.a. in the subsidy returns of 1436, was a feoffee and annuitant of Robert, Lord Willoughby of Eresby (d.1452), and William himself began his career in Willoughby’s service.
None the less, even with his wife’s inheritance, it was in Grimsby that the young Yerburgh made his career as he waited to inherit his patrimony. His father held property there, for he contributed 16d. to the expenses of its MPs in 1450, and this connexion explains why William was, for a fine of 40s., admitted to the town’s freedom on 16 Oct. 1449.
Later Yerburgh’s connexion with Grimsby lessened, perhaps because he had come into his patrimony. When, on 1 July 1455, he stood once more as a parliamentary candidate for the borough he polled only one vote, and although he contributed 6d. to the expenses of the borough’s representatives in the Parliament of 1459, he seems to have played no further part in the town’s affairs.
Despite his allegiance to the Lancastrian family of Welles, Yerburgh suffered no ill consequences as a result of the Yorkist usurpation. Indeed, by Michaelmas 1461 he was holding office as the King’s bailiff of the honour of Richmond soke of Gayton-le-Wold, but it is doubtful whether this is to be interpreted as a mark of royal favour. The Yerburghs were tenants of the soke and William’s father had held the same office in the early 1450s when the honour had been in the hands of Henry VI’s half-brother, Edmund Tudor, earl of Richmond (d.1456).
The Readeption of the following October marked a brief recovery of Yerburgh’s fortunes: in Hilary term 1471 he was suing pleas of account against his estate officials in the court of common bench. But his difficulties were soon renewed by Edward IV’s victorious return in the following spring. On 26 May a commission was issued for his arrest and those of other Lincolnshire supporters of the Readeption, such as John Truthall, Thomas Fitzwilliam II*, John Newport II and John Saynton†, and even though he was able to sue out a general pardon on 16 Apr. 1472 his involvement in the Welles rebellion cost him dear. In March 1473, with his son Richard, he entered into a bond in the large sum of 500 marks on condition that, within a month, he should make estate of all his lands to Sir William Hampton†, mayor of London, Sir William Taylor, and others, as security for the payment of £207 16s. in three instalments between May 1473 and February 1474. Clearly he had been forced to borrow on disadvantageous terms, presumably to pay for his pardon.
To add to Yerburgh’s troubles, in Easter term 1473 a plea of account was sued against him in the common pleas by the duke of Clarence, but death soon rendered such actions nugatory. He was alive in the following January when, with other feoffees of the attainted Richard, Lord Welles, he made a settlement upon Welles’s daughter and heiress and her husband, Richard Hastings, Lord Welles, but he does not appear in the records thereafter.