 Complete the following phrase:  John of Montfort ,  1295  26 September 1345, Château dHennebont, sometimes known as John IV of Brittany, and 6th Earl of Richmond from 1341 to his death. He was the son of Arthur II, Duke of Brittany and his second wife, Yolande de Dreux. He contested the inheritance of the Duchy of Brittany by his niece, Joan of Penthièvre, which led to the 