Tresithney came from a middling gentry family which took its name from the manor in the parish of Gwennap in western Cornwall. The family held some of their property from the powerful Arundells of Lanherne,
The Arundells aside, Tresithney also commanded the respect of others among his neighbours, and he is found attesting the deeds of important south-western families like the St. Aubyns of Combe-Raleigh, as well as those of lesser men.
The extent of Tresithney’s landholdings, at least some of which were situated near the Arundell seat at St. Columb Major, is obscure, but in 1451 his widow was thought to hold property worth 40s. in the county, suggesting that her late husband could command at the very least three times that sum.
When Tresithney died on 1 Sept. 1445 he was alleged to have held no lands. Instead, the escheator’s inquisition provided the occasion for a major survey of the estates of the Arundells of Tolverne, of which he had been the last surviving feoffee and which he had controlled during the minority of Sir Thomas’s son and heir John, still only 18 when Tresithney died.
