I mean forbidden jutsu are interesting and probably fun in some strange and sick ways. But, who is/are the author these jutsu. I mean somebody must have created and even tried these jutsu but who. And, why does it seem like Konoha have the largest collections these forbidden jutsu.

Are these spoils of war from other clans or ninja groups (during the constant war times)

or

Are these indications that Konoha wasn't as innocence as people are lead to believe in the beginning and were power hungry back then that they experimented with various things.........

Let's discuss..............