Quote Originally Posted by KCMmmmm
Here's the last part of my idea: how did Tobi get the Sharingan, if he isn't an Uchiha? Maybe he simply recovered the body of a fallen Uchiha (do we know any?), and took the eye. Maybe he was jealous of Nagato's doujutsu, or maybe he needed it for another reason?
Keeping up with his reasoning of becoming powerful to protect the whole country, maybe he did take the eye from a fallen Uchiha, having heard about the legacy of Uchiha Madara and the power he possessed. This would fit in with Tobi saying "The power of Uchiha Madara is mine!" without meaning that he is actually him. It would also fit in with trying to better Nagato's doujutsu if he was jealous and wanted to be the all-powerful saviour rather than being surpassed by someone he thought of as inferior.

It's all grasping at straws though.