Pierre Aycelin de Montaigut or Montaigu, Montagu, known as Cardinal de Laon, born between 1320 and 1325 and died 8 November 1388,[1] was a fourteenth-century French cardinal, who was the bishop of Nevers (1361–1371) and bishop of the Diocese of Laon (1371-1386), advisor to the king of Charles V and peer of France.

His autopsy proved that he was poisoned on 8 November 1388,[3] being buried in the abbey church of the priory of Saint-Martin-des-Champs in Paris.

[clarification needed][3] Brother of Cardinal Gilles Aycelin de Montaigu,[n 1] who was bishop of Thérouanne and Lord Chancellor of France between 1357-1358 and again in 1361.

Pierre Aycelin Montaigut was created a cardinal by Pope Clement VII of the Avignon Obedience in the Consistory of 23 December 1383.

[5] On 15 January 1388 the abbot of Saint-Denis, Guy de Monceau, accept the arbitration of the cardinal of Laon in the proceedings against the bishop of Paris, locked in the prison of the abbey.