What I don't understand is why people say that Madara could not live after so much time when he himself had told his life story to Sasuke clearly saying "I am Madara Uchiha."
Let's see we have a manga where :
1. People have no problem in exchanging eyes.
2. We saw a guy with his head chopped off and still be able to talk and attack
3. We saw a guy with 6 hearts.
4. We saw people having oversized racoons and demon foxes inside them.
5. We saw humans looking like sharks and snakes.
6. We saw a guy with a thousands of boulders dropped on his body , and after that he was still able to talk and breathe.
And you are still skeptical about Madara just living 100 freaking years? I don't know that's just beyond me lol
Now knowing that Madara had been the mizukage all this time we now have the missing parts of the story put together. Why had Zabuza hated his former village so much ~ because an outsider had become mizukage hence why he tried to kill him and he failed miserably(A ninja of Madara's Caliber probably didn't even take a sweat to defeat zabuza). The Kaguya clan's rebellion against the village , and why they were all killed. The Hidden mist's village brutality(Bloody Mist village rings a bell?). Also the Mist was a pretty small country and it is still considered one of the great 5 shinobi countries.