this was what I said some other posts in a other threads and got bashed:
Madara was the one that gave Nagato the rennigan because he awakened the rennigan due to Hashirama's DNA.
You have to pay attention to the time line of the story properly in order to realise the truth. Here is how the timeline flows:
He found and gave the rennigan to Nagato just before the 2nd shinobi world war or while the war was still going on. why did I say so? Answer: it is because in the timeline of Naruto, Nagato is way older than Obito and Jiraya found Nagato during the 2nd world war where/after they they fought Hanzo of the Salamander and where now known as the sennins. Jiraya trained Nagato, Yahiko and Konan for 3 years, after which he then returned to the leaf and Minato Namikaze became his apprentice and he taught him too.
On the other hand, he saved Obito during the 3rd shinobi war when he was much older and trained or passed some sharingan traits to Obito.
Another issue is that Madara was also wearing mask in his time after he left the village, when he exploited 4th Mizukage and helped Itachi kill the Uchihas because he hated them for abandoning him. But after he died, Obito/Tobi started wearing mask as well to pretend he was Madara, that is where the confusion came in.
You might argue that Madara still had his eyes (sharingan) when he saved Obito, but you have to Remember that Madara was the leader of the Uchihas, and he has so many sharingans in store. If Danzo could get that many sharingans on his arm, why wont the leader of Uchiha have other sharingans to his access (not even one?).
Madara already had his plan to be immortal which is why he gave Nagato that rennigan as an Uzumaki, he would have more chakra reserves to train and explore the powers of the eyes in order to awaken him later.
He then pass on his dreams to Obito as a master would pass his visions to his apprentice, and told him about his plan. So Tobi would have rejected it first but after he found out the world is full of pain after he lost Rin then he starts listening to Madara and started training before he started pretending to be Madara, and leading akatsuki; which in fact was set up by Madara himself and not Tobi.
Hope this help u understand a bit more and have now made people that said Nagato awakened rennigan himself awaken from their self casted genjutsu.... I bet none of u can stand up and make those threads anymore
I am presently happy to say; Now all these theories have been backed up by Kishi when u read 602
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