Which philosopher concluded that government could be best kept under control if it were divided into three separate branches of government?

I believe that the best answer for this question is Baron de Montesquieu. He was a French philosopher who lived in the Age of Enlightenment. He popularized the idea of dividing the government into three separate powers, which is also known as the "trias politica" or the "tripartite system." The three systems that he supported where the legislature, executive, and judiciary systems. Hope this helps.

Islam was founded in the same region