When John’s father died in 1413 most of his property passed to his eldest son, William, although the manor of Baynton, valued at £5 p.a. in the previous year, together with that of Leigh in Westbury, were both inherited by the future MP. Besides these, he held in right of his first wife property in Wilton and Ugford, which, however, he was to relinquish in 1439 in return for a rent of five marks a year for the term of her life.
Rous may have owed his only return to Parliament to his connexion with Sir Walter Hungerford, in whose retinue he had served at the battle of Agincourt. His experience in this respect was no doubt recalled in December 1419, when the j.p.s for Wiltshire were required to send to the Council the names of 12 men-at-arms considered best able for military duties: John and his brother William both figured on the list compiled. John attended the Wiltshire elections to the Parliaments of 1422, 1425, 1426, 1431, 1433, 1447, 1449 (Nov.) and 1450, in the meantime, in 1434, being one of those gentry of the shire required to take the oath imposed by Parliament against maintenance of malefactors.
In fact, Rous himself had already been party to lawless behaviour in the county. He had helped his brother to retain possession of the manor of Great Charfield in 1431, when the Beverleys came armed to support their title, only to lose control of it to another claimant, Thomas Tropenell, later. William was accused in Tropenell’s cartulary of lechery and adultery. Certainly, bastards figured often in accounts of the family: not only did John’s father and brother beget several, but he himself produced an illegitimate son. (William also, allegedly through dissipation, disposed of most of the Rous lands to Sir William (by then Lord) Hungerford.)