The one to kill is zoroaster. After him, abraham (assuming he existed), after hi

The one to kill is zoroaster. After him, abraham (assuming he existed), after him Saul. After him Augustine. After him, Constantine before he ascended the throne. After him Muhammed (probably the most important). After him, Napoleon, thereby preventing the need to unify germany. After him Marx. The only reason to get to hitler is because these people existed.