Fitzwilliam greatly advanced his family’s fortunes in a lengthy and notably successful legal career. He was probably studying at Gray’s Inn by Easter term 1449 when he appeared in person in the court of common pleas to sue a husbandman of Mablethorpe on a plea of detinue of chattels.
Fitzwilliam’s service in the Parliament which attainted the Yorkist lords and his appointment to the Lancastrian commission of array of December 1459 implies that his political sympathies lay with Lancaster. Yet his nomination to the Yorkist commission of arrest of the following November suggests that he was not considered a partisan of that cause. Indeed, unlike his father, he appears to have had no difficulty adapting to the new regime. He took the precaution of suing out a pardon in February 1462 and was reappointed to the Lindsey bench a year later.
Nevertheless, despite this evidence that Fitzwilliam was finding favour under the Yorkists, his family’s association with their baronial neighbours, the Lords Welles, who had suffered attainder in 1461 and who retained their Lancastrian loyalties despite their full restoration in 1467, were soon to pose him a serious problem of loyalties. In February 1468, with his father, his first cousin, Sir Thomas Dymmok (who was also the brother-in-law of Richard, Lord Welles), and William Yerburgh*, he acted with Lord Welles to make a settlement in favour of Margaret, duchess of Somerset, the widow of Lionel, Lord Welles. He and his father were also Welles feoffees in manors in Cambridgeshire and Northamptonshire, and there can be little doubt that they were trusted servants of the family.
Like most others, however, Fitzwilliam quickly reconciled himself to the restored Yorkists. On 10 Dec. 1471 he sued out a general pardon which, for additional security, he had enrolled on the patent roll; in the following July he reappeared on the ad hoc commissions of Lincolnshire government; and in November 1475 his restoration was completed by reappointment to the Lindsey bench. His re-establishment may have owed something to a connexion formed with the Hastings family. Joan, daughter and eventual heiress of the ill-fated Richard, Lord Welles, had married Richard, younger brother of the King’s intimate, William, Lord Hastings, and when, in February 1476, our MP secured a royal licence to found a chantry in the parish church of Alford, near Mablethorpe, the Hastings brothers were named among those for whom prayers were to be endowed. Fitzwilliam’s election on 12 Jan. 1478 to the Parliament which oversaw the downfall of George, duke of Clarence, is another indirect indication that he had now found favour with the Crown.
Further promotion within the legal profession followed. On 19 June 1483 the common council of London elected Fitzwilliam as recorder of the City in succession to Sir Humphrey Starky, who had been appointed chief baron of the Exchequer four days earlier. It was unfortunate for him that this promotion came at a time of such acute dislocation in national politics, but it may not have been coincidence. It has been suggested that his appointment was a reflection of an earlier association with Richard, duke of Gloucester. Certainly, his service as a duchy of Lancaster apprentice must have led him into contact with Gloucester, who was chief steward of the north parts of the duchy, and, if the traditional Fitzwilliam pedigree is to be credited, Thomas’s wife was the daughter of one of the duke’s leading northern followers, Sir James Haryngton†.
None the less, whatever Fitzwilliam’s private views about the validity of Richard III’s right to the throne, they did not prevent him playing an active role in the affairs of the reign. On 5 July 1483, as the coronation procession moved through Cheapside, he, as recorder, made a brief speech and presented a purse of 1,000 marks to the King and later one of 500 marks to the queen as the City’s contribution towards the costs of the coronation. In the following October he was elected as MP for London in a continuation of the recently-established practice by which the City returned its recorder (although the Parliament never assembled because of Buckingham’s rebellion).
Fitzwilliam’s importance as a man of affairs had been recognized by the Crown on 21 Feb. 1484 with the grant of an annuity of 20 marks from the Lincolnshire honour of Bolingbroke; and on the following 1 Apr. he was granted a ten-year lease of the manor of Saltfleetby at an annual rent of £20 11s. 8d., either a renewal or re-grant of a lease he had held as early as 1467.
Fitzwilliam’s Speakership marked the high point of a successful career. By 1489 he must already have been in his early 60s and, although he continued to be appointed to local commissions as late as July 1496, he last occurs as recorder in October 1494 and had been replaced in the office by another Lincolnshire man, Robert Sheffeld†, by the following September.
Fitzwilliam’s will was also concerned with ensuring an adequate endowment for his widow and two younger sons. At his death he was seised of a landed estate in Lincolnshire conservatively valued, in his inquisition post mortem, at £79 p.a. The bulk of this estate appears to have come to him by way of inheritance for, despite the wealth that a successful career must have brought him, his purchases appear to have been confined to small parcels of land in the immediate neighbourhood of his inherited properties. The exception was the ‘place’ he bought at Stepney in Middlesex, no doubt to serve as his London residence while he was recorder. This he did not intend to form a long-term addition to his family’s lands for he provided for its sale in his will. Other purchases made up the endowment of his youngest son William, who was to have, in tail-general, lands in Mablethorpe and Trusthorpe, valued at eight marks p.a. His other surviving son, George, was to be endowed out of the Fitzwilliam patrimony, holding, again in tail-general, the family lands in Louth with the exception of the capital messuage there which was to be the residence of our MP’s widow. Sir Thomas was careful to ensure that she received her full common-law entitlement: his executors were instructed to allow her a third of his purchased lands as well as a third of all the lands of which he or his feoffees were seised at his death, regardless of any assignment contained in his will save only the alienation of land in Little Carlton worth 26s. 8d. to the chantry he had founded at Alford.
Fitzwilliam’s importance in the later part of his career is reflected in the quality of his connexions. At his death his feoffees were headed by John Blithe, bishop of Salisbury, John de Vere, earl of Oxford, and John, Lord Dynham, while among those for whom he acted as a feoffee in the later years of his career were numbered Edward Grey, Viscount Lisle, Sir Robert Tailboys†, Sir Henry Vavasour†, Sir John Markham, former c.j.KB, Sir Humphrey Starky, whom he had succeeded as recorder, and John Stanhope*.
Sir Thomas died on 4 Mar. 1497, and it seems he was buried in the church of Mablethorpe rather than, as his will had directed, in the nearby abbey of Hagnaby.
