Akademik

Diffidatio
Lit. 'defiance'. A statement in which allegiance to a lord was renounced and that renunciation justified. Such a statement was the only way by which the break from a lord could legally be accomplished. In 1138, Robert, earl of Gloucester, sent his diffidatio to King Stephen 'according to ancient usage, [and] renounced his fealty and friendship, and annulled his homage'. Gloucester was breaking with Stephen for the latter's breach of promise and oath to acknowledge Matilda as true heir of Henry I, as Henry demanded before his death (1135). At the deposition of Edward II in January 1327 Sir William Trussell verbally renounced all homage and allegiance to Edward in person, ex parte tocius regni (on behalf of the whole realm). The *steward of the household, Sir Thomas Blount, broke his staff of office, declaring the royal household defunct. -
Cf. Homage1

Dictionary of Medieval Terms and Phrases. .