What three branches of government does Montesquieu say must be separated to have liberty

Legislature, Executive and Judiciary

Explanation:

In the 18th Century Montesquieu said that these three branches of government should exercise only its function, and that would lead to what he believed liberty is.

In its major work, the Spirit of Law (L'Esprit de Lois, 1748), for the first time, he emphasized the idea of the separation of powers into executive-administrative, judicial and legislative, as is still known today in the practice of democratic states. He is also known for his concept of federalism. In the aforementioned section, he also talked about how different geographical conditions can influence the character of the rule. Many of his ideas will be found in the French Declaration on the Rights of Man and Citizen.