Board Thread:Naruto Discussions/@comment-3965545-20161228130925/@comment-1512913-20170101114148

The only reason pretty much why Asura being a Kurama jinchuuriki is not accepted as true at the moment is because Mito was said to be the first.

But need I remind you that Madara and Izuna were said to be the first Mangekyou Sharingan users as well, which turned out untrue.