In an epic battle of legend, Sir Cadogan rides into battle with the infamous Wyvern of Wye. He nearly loses the battle — his horse is eaten, his helmet melted, and his wand broken — but he finds a fat gray pony in a nearby field and rides back to what he could only have assumed would be a heroic death. In fact, his splintered wand pierces the tongue of the wyvern and ignites the noxious gasses in its gullet. The wyvern explodes and Sir Cadogan’s reckless bravery is immortalized in a portrait which still hangs in the South Tower of Hogwarts castle (Pm).
Sir Cadogan was a Knight of the Round Table and a friend of Merlin, which places him in the 11th century as far as it is possible to deduce.