I believe Notch because of the stories i've heard. I have heard that, on the first day, Notch created Minecraft. Later on, in 2009, a user with the name of Herobrine joined a minecraft world. As ExplodingTNT explains it, Herobrine changed all of the mobs face texture to his own. As a result of that, he was removed. You can't remove yourself, even if your the creator of Minecraft. That is why I think Notch created Minecraft.
ExplodingTNT's video: https://www.youtube.com/watch?v=D3a1ZR6Y2YQ