French civil war gives England diplomatic leverage

Charles VI's recurring incapacity leaves Burgundian and Armagnac factions fighting for control of France. Their rivalry brings atrocities against French communities, making the conflict more than a court quarrel. English forces can sell support to one side and then switch when the other offers more money or territory. Henry V's 1414 agreement with the Armagnacs consequently restores English holdings in southwestern France before his invasion. French fragmentation gives the English king both diplomatic and military leverage.