John was the eldest of three children born to Duchess Alix and her husband and co-ruler, Duke Peter I.

His father, who had reigned as duke due to his marriage to Alix, ruled as regent until John reached adulthood.

[2] In 1268, Henry III granted the earldom of Richmond to John,[3] and the title continued in his family, through frequent temporary forfeitures and reversions, until 1342.

[4] He joined Louis IX of France in the Eighth Crusade in 1270, and survived the plague that killed the king.

[5] In 1236 John married Infanta Blanche, daughter of King Theobald I of Navarre.