An old but undistinguished family, the Chyvalls had possessed lands at Bow Brickhill in Buckinghamshire during the thirteenth and early fourteenth centuries,
As minor landowners, the Chyvalls were never foremost among the Hertfordshire gentry, and it is likely that Chyvall owed his seat in the Commons to his status as an esquire of the King’s household.
Chyvall had certainly joined the royal establishment by February 1430, when together with another of its esquires, Ralph Babthorpe, he indented to accompany Henry on his coronation expedition to France. Each undertook to bring three mounted archers and to muster at Dover on 1 May, the Crown agreeing in return to pay daily wages of 12d. to each of them and 6d. to each of their archers.
It is possible that his status as a Household man emboldened Chyvall – not known to have received any grants of land from the Crown – to make a speculative bid for estates in Buckinghamshire some two years after obtaining his Stogursey annuity. By 1440 he had begun lawsuits in the court of common pleas against John Helwey and the widowed Elizabeth Ragon, mother of the recently deceased John Ragon* and sister and coheir of the late Thomas Wydeville*, for committing waste on the manor of ‘South Caldecote’, Buckinghamshire. It is likely that the manor was the Wydeville lordship of Caldecott at Bow Brickhill, a property to which he could have had no valid claim even though his ancestors had once possessed an estate in that parish.
In spite of his membership of the unpopular Household, Chyvall retained his place on the Hertfordshire bench throughout the political crises of the late 1440s and early to mid 1450s. Although a j.p., he was appointed to only three ad hoc commissions in his native county and was not active as a feoffee there. The only parliamentary election he certainly attested was that to the Parliament of 1447, the assembly called to bring down the court’s opponent, Humphrey, duke of Gloucester.
In his will, dated 24 Feb. 1457 and proved on 9 Sept. 1458,
