The son of a successful lawyer, Fynderne inherited a tradition of loyalty to the Lancastrian monarchy in whose cause he was to meet his death. His father was originally from Derbyshire but established himself in southern England.
The marriage is likely to have occurred around May 1431, when a formal quitclaim of lands in Weston, Cambridgeshire, was made to Thomas, along with his parents and his new wife, and two distinguished feoffees, the duke of Bedford and William Allington I*.
The circumstances of Fynderne’s knighthood are unknown but he had probably earned it by serving in France, possibly under Humphrey, duke of Buckingham, at Calais. Surviving indentures show that the duke retained him, with a fee of £10 p.a. from his Suffolk estates, in 1447, but these are likely to refer to service in England, and do not prove that they were unconnected before this date.
As far as Essex was concerned, Fynderne’s chief link with the county was his wife’s inheritance, although he never held any office there. His first known involvement in local politics was the Berkshire election to the Parliament of 1435. In spite of not having attained his majority, he was one of 30 named attestors who witnessed the return to the Commons of his father and William Perkins* as that county’s knights of the shire. So far as is known, Fynderne’s Membership of the Parliament of 1447 was his first public office. If resident in Essex at the time of his election, he had become primarily identified with Cambridgeshire before the end of the decade, as represented by his appointment to an ad hoc commission there in September 1449, to his return as a knight of the shire for that county in the consecutive Parliaments of 1449 and 1449-50 and his appointment as a feoffee by one of its most prominent esquires, Laurence Cheyne*.
Owing to his service in France, Fynderne’s career at a local level was curtailed for much of the 1450s. In the summer of 1451 he crossed the Channel with 200 men provided by the city of London for the defence of the pale of Calais, threatened by a French invasion,
As letters of protection he received prior to crossing from England to France in mid 1453 and again in the following year indicate,
In the following autumn the duke of Buckingham’s friend and annuitant,
It was also in the autumn of 1456 that the King, having regained the political initiative against York and his allies, dispatched a privy seal letter to Fynderne, then in Suffolk, and appointed him a j.p. in Cambridgeshire for the first time. While the contents of this and two other such letters the MP received over the following two years are unknown, they are probably a sign of his growing identification with the Lancastrian Crown.
During 1459 political tensions in England increased, reaching a height when York and his allies were excluded from a great council called to Coventry that summer. When fighting finally broke out, Fynderne, a soldier and a ‘King’s knight’,
Within weeks of Edward IV’s accession, the authorities began the process of taking action against Fynderne on account of several bonds in statute staple to which he had put his name at Westminster. The circumstances in which he had entered these securities are unknown. One of these was a bond for 50 marks that he and others had entered into with John Lok† of London in March 1460. Two others, bearing the like penalty, were far less recent. Both dated 27 Jan. 1452, these were securities that Fynderne and several associates acting on his behalf, Lawrence Cheyne, William Allington II* and John Ansty*, had given to Ansty’s son-in-law, the late Henry Langley (nephew of the former bishop of Durham, Thomas Langley, and lord of the manor of Lolworth in Cambridgeshire) and the Londoner, John Bedham. They had been intended to guarantee that they would pay Langley and Bedham 50 marks at Christmas 1452 and the same amount a year later, but in November 1461 the Chancery ordered the sheriff of Cambridgeshire and Huntingdonshire, John Styuecle*, to take action for the non-payment of the 100 marks in question. Early in the following year, by which stage Fynderne had been attainted in Edward IV’s first Parliament, Styuecle seized the Fynderne manors at Weston Colville and Willingham for the King, who soon afterwards granted the MP’s estates in Cambridgeshire to Thomas St. Leger†.
In April 1462 the exiled Fynderne accompanied Queen Margaret to France, advising her as one of her councillors on the treaty she signed with Louis XI at Tours on 28 June.
By the following spring Fynderne was back in northern England, for he was one of the leaders of the Lancastrian force that attempted to ambush John, Marquess Montagu, at Hedgeley Moor on 25 Apr. 1464. On 15 May, however, it was Montagu’s turn to launch a surprise attack and he overwhelmed a smaller Lancastrian force at Hexham. Fynderne and two fellow diehards with whom he had shared exile in France, the Lords Roos and Hungerford, managed to escape the battlefield but two days later they were caught hiding in a wood, taken to Newcastle and executed.
