 Charles ' illness created a power vacuum that eventually led to the Armagnac – Burgundian Civil War between supporters of his brother , Louis of Orléans and the royal dukes of Burgundy . Isabeau shifted allegiances as she chose the most favorable paths for the heir to the throne . When she followed the Armagnacs , the Burgundians accused her of adultery with Louis of Orléans ; when she sided with the Burgundians the Armagnacs removed her from Paris and she was imprisoned . In 1407 John the Fearless assassinated Orléans , sparking hostilities between the factions . The war ended soon after Isabeau 's eldest son , Charles , had John the Fearless assassinated in 1419 — an act that saw him disinherited . Isabeau attended the 1420 signing of the Treaty of Troyes , which decided that the English king should inherit the French crown after the death of her husband , Charles VI . She lived in English @-@ occupied Paris until her death in 1435 . 
