Itachi Uchiha is one of the major antagonists in the Naruto series who was initially introduced as a protagonist. He is an Anbu captain turned rogue ninja who wishes to change the world by destroying it, establishing a utopia free from lies and wars.
He also sported the typical Akatsuki hood and a shredded Konoha forehead protector, signifying his rifts with the village as a member of Akatsuki.
His past is told in the form of tragic backstories. As a child, Itachi was kind and had more friends than Sasuke did. His life changed when he met Madara Uchiha at the age of seven. At that moment, they made an oath to become brothers which they kept for their whole life.
The best evidence for this is how Itachi put his faith in Naruto by telling him everything about his past which lead the latter to defeat Tobi.
Itachi’s story ends with him being one of few survivors from the Leaf Village’s massacre. He dies after using his Mangekyō Sharingan on Sasuke revealing that he truly did love him until his last breath.
Even though he is considered a sinner by most people who knew him, Itachi is remembered by the world as a hero who saved it from the darkness of Madara.