Arthur is the main character in Idylls of The King. He is the King of England and has many strengths and weaknesses that define his character.
King Arthur is the son of Uther Pendragon. He was born when the king lay with the wife of a duke he killed in a battle. However, this action will come back to bite Arthur later.
Arthur is a good king. He is kind, resolute, and above all, victorious. All the battles he participated in the book, he won, and he fought many battles.
However, Arthur was most successful because of the people around him, the legendary Round Table. These knights were what helped him win the battles, and helped him govern the kingdom (along with Merlin).
However, Arthur wasn't perfect, as he laid with someone else's wife and got Mordred, who would later kill him. He later imitated Herod in killing all the babies born on May Day to get rid of Mordred, but was unsuccessful and paid for it with his life.