 Madog made an alliance with Ranulf de Gernon, 4th Earl of Chester, but Owain defeated them at the Battle of Ewloe (Coleshill) in 1150 and took possession of Madog's lands in Iâl ().In 1157 when King Henry II of England invaded Gwynedd he was supported by Madog, who was able to regain many of his Welsh lands.Even so, he retained the lordships of Oswestry and Whittington.