Uncovered in February 1462, the Oxford Conspiracy was a vague Lancastrian plot that centered on John de Vere, twelfth earl of Oxford (c. 1408-1462), and his eldest son, Sir Aubrey de Vere. Because the failed plot led to the executions of both de Veres, the Oxford Conspiracy not only contributed to the political instability that marked the early 1460s, it also transformed the earl's surviving son, John de VERE, thirteenth earl of Oxford, into an implacable foe of the house of YORK.
During the winter of 1461-1462, rumors of Lancastrian intrigues swept England. Jasper TUDOR, earl of Pembroke, was said to be planning a descent on WALES; Henry BEAUFORT, duke of Somerset, was thought to be preparing an invasion of East Anglia; and a large army of Spaniards and Frenchmen was believed to be poised for a landing in Kent. Another persistent rumor claimed that the earl of Oxford, a powerful Essex magnate and a staunch supporter of HENRY VI and the house of LANCASTER, was behind a series of attacks launched against English coasts by Lancastrian raiders operating out of FRANCE. Thus, when Yorkist agents intercepted letters passing between Oxford and Queen MARGARET OF ANJOU, the discovery only confirmed Yorkist suspicions about the earl's activities.
Arrested on 12 February 1462, Oxford and his son Aubrey were confined to the TOWER OF LONDON. The Yorkist regime, fearful of both internal rebellion and external invasion, dealt quickly and harshly with the de Veres. Tried for treason before John TIPTOFT, earl of Worcester and constable of England, both men were condemned, along with several accomplices who were likely members of Oxford's AFFINITY. The exact nature of Oxford's plotting is unclear. He appears to have been charged with organizing some type of Lancastrian invasion and also possibly with conspiring to lead a party of armed RETAINERS, ostensibly raised on the king's behalf, to intercept and kill EDWARD IV as he rode north to meet Lancastrian incursions from SCOTLAND. One source claims that Aubrey de Vere informed on his father, accusing the earl of planning a Lancastrian landing on the Essex coast. However, such a betrayal, given Sir Aubrey's own condemnation and what is known of his character, seems unlikely.
Sir Aubrey died first, suffering the full horror of execution for treason-hanging, drawing, and quartering-at Westminster on 20 February. Being a member of the PEERAGE, Oxford had his sentence commuted to beheading, which he suffered on 26 February. Because no ATTAINDER was passed against his father, John de Vere, the second son, was allowed to assume his father's title and estates until he was himself arrested for Lancastrian plotting in 1468. Although soon released, the thirteenth earl of Oxford was thereafter a constant opponent of every Yorkist regime.
Further Reading: Seward, Desmond, The Wars of the Roses (New York: Viking, 1995).