One of several sons of John Leventhorpe, who brought his family to prominence in the early fifteenth century as receiver-general of the duchy of Lancaster and executor of the first two Lancastrian Kings, Robert was named after his grandfather. His elder brother John was destined to follow their father as a professional administrator in the service of the duchy, but Robert himself was apparently intended for a military career – at least initially. Perhaps through the auspices of his father’s friend Robert Southwell he came to the attention of John Mowbray, earl of Norfolk and Earl Marshal, and in 1415 enlisted in the earl’s retinue for Henry V’s invasion of Normandy. He fought at Agincourt in Mowbray’s company. Two years later, on 30 Sept. 1417, the earl granted him and his wife Elizabeth (whose parentage is not known) an annuity of 20 marks for term of their lives. Robert went on to serve under the same magnate in the garrison at Pontoise in the summer of 1422, but did not return to France again after the King’s death. Rather than joining his lord on the expedition of 1423, he stayed behind at Sandwich, attending on the countess of Norfolk, when the earl set sail in May that year.
Robert’s second marriage, to Joan Waleys, probably came about through his family’s connexions with the gentry of Hertfordshire, for Joan’s mother was an heiress with substantial estates in that county. Joan herself was one of four daughters of John Waleys of Glynde, who following the deaths of their father and only brother John (a minor) fell heir not only to the Sussex estates of the Waleys family but also to those of their maternal grandparents, the wealthy Sir Robert Turk and Beatrice Kendale, in Hertfordshire, Bedfordshire, Hampshire and London.
A more serious dispute focused on the wardship of the next male heir to the valuable manor of Glynde, the girls’ cousin William Waleys, later held to be mentally unsound (and called ‘the idiot’ in the family pedigree). On this matter our MP’s father John Leventhorpe fell out with Robert, 4th Lord Poynings, and the two men were summoned to appear before the Council in the Star Chamber on 24 Feb. 1425. There they were required to accept the award of the bishops of Winchester (the chancellor), Durham and Worcester and Lord Scrope in their dispute over custody of the heir, whom Poynings asserted had been unjustly detained by his opponent. It would seem that a compromise was reached, for a few days later, on 1 Mar., our MP and William Holgrave were committed keeping of the lands formerly held by his late mother-in-law and her son John Waleys for as long as these remained in the King’s hands, together with the marriages of the two younger coheiresses, for which keeping and marriages they agreed to pay a flat sum of £100. If the lands proved to exceed the sum of £54 p.a. in value they were to answer to the Crown for any surplus revenues.
Leventhorpe had attested the Hertfordshire electoral returns to Parliament at Hertford on 23 Sept. 1423, and successfully sought election as a knight of the shire himself some 18 months later, on 5 Apr. 1425, shortly after he obtained his grant at the Exchequer. Perhaps the difficulties he and his father had encountered in this regard prompted him to do so. His father was the first to witness the parliamentary indenture. But Robert did not long survive after his appearance in the Commons. He was present again at the Hertfordshire hustings on 7 Feb. 1426,
