The tales "Culhwch and Olwen" and "The Dream of Rhonabwy" have interested scholars because they preserve older traditions of King Arthur. The subject matter and the characters described events that happened long before medieval times. After the departure of the Roman Legions, the later half of the 5th century was a difficult time in Britain. King Arthur's twelve battles and defeat of invaders and raiders are said to have culminated in the Battle of Badon.