Whoso Pulleth Out This Sword of this Stone and Anvil, is Righties King Born of All England.
Merlyn impacted the Wart the most out of the characters due to the education he gave to Wart. Merlyn said on page 46, "Education is experience, and the essence of experience is self-reliance." Merlyn educated the Wart all throughout his years by changing him into different animals to prepare him for his future as King Arthur.
Sir Ector impacted the Wart's life since the very beginning when he took him in and treated him as a son. On page 134, Sir Ector "stood gloomily for a moment, watching his two boys trying to catch the last leaves in the chase." This demonstrates that Sir Ector sees both of the boys as his own sons, and no different. Throughout his childhood, the Wart has looked up to Sir Ector and admired his abilities especially his knightly skills.
Kay impacted Wart by teaching him how to be honest and compassionate no matter who you are. On page 206, Kay said, "I am a liar. Wart pulled it out." Although it seems like Kay isn't a good older brother, he still managed to give Wart proper credit for things he accomplished, such as pulling the sword out of the stone. Wart has always looked up to Kay, despite his actions.