This argues that England King Edward III’s imprisonment of Joan of Flanders, Duchess of Brittany and Countess de Montfort during the Hundred Years War was not for her so-called madness, but was political. Joan of Flanders, who had led a defense of the castellany of Hennebont that routed the French and saved Montfortist Brittany, abruptly vanished from public life in the Fall of 1343. While it has been presumed that she succumbed to mental illness, the nature of confinement, its secrecy, and its political implications indicate forcible confinement. Conflict broke out in Brittany after a succession crisis that pitted the pro-English Montfortist faction against the Blois-French forces. Joan of Flanders, wife of John de Montfort, came into prominence following her husband’s imprisonment. After departing for England with her children, she disappeared from society being sequestered in the Tickhill Castle in Yorkshire, England. Control of the Honour of Richmond and the Duchy of Brittany are overlooked elements in the captivity of Joan of Flanders. Edward III was suzerain of Brittany and he had the heirs, Joan’s children, in royal wardship. Moreover, the date of John de Montfort’s release from prison and whether he was an Earl or a Count of Richmond are essential to the story. For more than a half-century, English kings had been trying to reclaim the Honour of Richmond. The curious timing of Joan of Flanders’ castle confinement relative to John of Gaunt’s creation as Earl of Richmond in her husband’s place reveals the motivations of Edward III in his war with France and desire for English hegemony on the continent. Edward III was not above neutralizing an opponent for political expediency, whether enemy, ward or widow. A political pawn in Edward III’s quest to recapture the Angevin Empire, Joan of Flanders fell victim to the politics of fourteenth-century war and conflict. ; History, Department of