Roger Mortimer, 1st Earl of March on 22 May 1306, in a lavish ceremony in Westminster Abbey with two hundred and fifty-nine others, he was knighted by Edward and granted livery of his full inheritance. His adult life began in earnest in 1308, when he went to Ireland in person to enforce his authority. This brought him into conflict with the de Lacys, who turned for support to Edward Bruce, brother of Robert Bruce, King of Scots. Mortimer was appointed Lord Lieutenant of Ireland by Edward II on 23 November 1316. Shortly afterwards, at the head of a large army, he drove Bruce to Carrickfergus and
John de Warenne, 7th Earl of Surrey Scottish throne, accompanied him on his campaign in Lothian. Balliol created Warenne earl of Strathern, but this was in name only for the properties of the earldom were held by the Scots. Warenne died in 1347 and is buried at the monastery of Lewes. He was succeeded as earl by his nephew Richard Fitzalan, who was also earl of Arundel. On 25 May 1306 Warenne married Joan of Bar, daughter of count Henry III of Bar and Eleanor of England, eldest daughter of king Edward I of England. The two were soon estranged and lived apart, and had no children,