[1] He received Artois as an appanage, in accordance with the will of his father (died 1226) on attaining his majority in 1237 (aged twenty-one).

On 14 June 1237 Robert married Matilda, daughter of Henry II of Brabant and Marie of Hohenstaufen.

[3] They had two children: While participating in the Seventh Crusade, Robert died while leading a reckless attack on Al Mansurah, without the knowledge of his brother King Louis IX.

[6] Emboldened by his success, Robert, the Templar knights, and a contingent of English troops charged into the town and became trapped in the narrow streets.

[6] According to Jean de Joinville, Robert defended himself for some time in a house there, but was at last overpowered and killed.