Conflict with Orléans
John inherited the Duchy of Burgundy on 27 April 1404 upon the death of his father, Philip the Bold and the counties of Burgundy, Flanders and Artois on his mother's death on 16 March 1405. He almost immediately entered into open conflict with Louis I, Duke of Orléans, the younger brother of the increasingly disturbed King Charles VI of France. Both men attempted to fill the power vacuum left by the demented king.
John played a game of marriages by exchanging his daughter Margaret of Burgundy for Michelle of Valois, who would marry his heir, Philip the Good, Count of Charolais. For her part, Margaret was married to Dauphin Louis, Duke of Guyenne, the heir to the French throne from 1401 until his death in 1415. For all his concentration on aristocratic politics, John nonetheless did not overlook the importance of the middle class of merchants and tradesmen or the University of Paris.
Louis I, Duke of Orléans tried to gain the favour of the wife of Charles VI, Queen Isabeau, and may have become her lover. After his son-in-law, the Dauphin Louis, was successively kidnapped and recovered by both parties, the Duke of Burgundy managed to gain appointment by royal decree—during one of the king's "absent" periods when mental illness manifested itself—as guardian of the Dauphin and the king's children. This did not improve relations between John and the Duke of Orléans. Soon the two rivals descended into making open threats. Their uncle, John, Duke of Berry, secured a vow of solemn reconciliation on 20 November 1407, but only three days later, on 23 November 1407, Louis was brutally assassinated in the streets of Paris. The order, no one doubted, had come from the Duke of Burgundy, who shortly admitted to the deed and declared it to be a justifiable act of "tyrannicide". According to Thomas Walsingham, Orléans had simply received his just desserts as he had been "taking his pleasure with whores, harlots, incest" and had committed adultery with the wife of an unnamed knight who had taken his revenge by killing him under the protection of the Duke of Burgundy. After an escape from Paris and a few skirmishes against the Orléans party, John managed to recover the king's favour. In the treaty of Chartres, signed on 9 March 1409, the king absolved the Duke of Burgundy of the crime, and he and Louis' son Charles pledged a reconciliation. A later edict renewed John's guardianship of the Dauphin.
He moved further closer to securing the Regency for himself when he had Jean de Montagu, Grand Master of France and the king's long standing favorite and administrator aligned with the Orléanists, arrested during another one of Charles' manic episodes, and after an expedited summary trial carried out by the Burgundian-aligned politicians, Montagu was beheaded at the Gibbet of Montfaucon on 17 October 1409.
Even with the Orléans dispute resolved in his favour, John did not lead a tranquil life. Charles, the son and heir of the murdered Duke of Orléans, was only 14 at the time of his father's death and was forced to depend heavily on allies to support his claims for the property that had been confiscated from him by the Duke of Burgundy. Chief among these allies was his father-in-law Bernard VII, Count of Armagnac. Because of this alliance, their faction became known as the Armagnacs in opposition to the Burgundians. With peace between the factions solemnly sworn in 1410, John returned to Burgundy and Bernard remained in Paris, where he reportedly shared the Queen's bed. The Armagnac party was not content with its level of political power, and after a series of riots and attacks against the citizens, John was recalled to the capital, then sent back to Burgundy in 1413. At this time, King Henry V of England invaded French territory and threatened to attack Paris. During the peace negotiations with the Armagnacs, Henry was also in contact with John, who was keen to wrest control of France away from King Charles VI. Despite this, he continued to be wary of forming an alliance with the English for fear of destroying his immense popularity with the common people of France. When Henry demanded Burgundy's support for his claim to be the rightful King of France, John backed away and decided to ally himself with the Armagnacs. Although he talked of helping his sovereign, his troops took no part in the Battle of Agincourt in 1415, although two of his brothers, Anthony, Duke of Brabant, and Philip II, Count of Nevers, died fighting for France during the battle.