After March 1337, these manors were transferred to the new Duchy of Cornwall created by King Edward III to provide financial support to his son Edward, the Black Prince (1330–1376).
These manors were referred to as assessionable manors because they were leased under assession leases, which were renewed periodically.
[1] The table below shows the 17 Antiqua maneria, including the number and status of Customary tenants in the early fourteenth century.
The manors vary greatly in both size and importance.
[2] Conventionarii = Conventionary tenants; Villani = Villeins; Nativi = Villeins; Liberi Conventionarii = Free tenants; Nativi Conventionarii = Conventionary tenants; Nativi de Stipite = Villeins by descent