He was succeeded by his uncle, Philip, whose contested legitimacy led to the re-affirmation of the Salic law, which excluded women from the line of succession to the French throne.

The child mortality rate was very high in medieval Europe and John may have died from any number of causes, but rumours of poisoning spread immediately after his death (including one which said that he had been murdered with a pin by his aunt),[5] as many people benefited from it, and as John's father had also died in strange circumstances.

The king's brother, Philip the Tall, was in charge of the regency of the kingdom against his uncle Charles of Valois.

Philip ascended the throne at the expense of John's four-year-old half-sister, Joan, daughter of Louis X and Margaret of Burgundy.

[7] In The Man Who Believed He Was King of France, Tommaso di Carpegna Falconieri suggests that Cola di Rienzo manufactured false evidence that Baglioni was John the Posthumous in order to strengthen his own power in Rome by placing Baglioni on the French throne.

Shortly after they met in 1354, di Rienzo was assassinated, and Baglioni waited two years to report his claims.