 Barbara Tuchman postulated that they both refused the office because they knew the King was ailing and a regency under the Dukes of Anjou, Berry and Burgundy was coming and they didn't want the political enmity the function brought with it.When Charles V died in 1380, his heir, Charles VI of France was still a minor.Sancerre took part in the siege of Montguyon in 1380.