Question: who created separation of powers and checks and balances?
Answer: Montesquieu in the Enlightenment

separate the powers and guarantee their independence but to give the various branches the constitutional means to defend their own legitimate powers from the encroachments of the other branches. They guarantee that the powers of the State have the same weight (co-equal), that is, to be balanced, so that they can limit each other, avoiding the abuse of state power. the origin of checks and balances, like separation of powers itself, is specifically credited to Montesquieu in the Enlightenment (in The Spirit of the Laws, 1748), under this influence was implemented in 1787 in the Constitution of the United States.