“John Locke was born in 1632 and died in 1704; he personified the liberal tendencies against the absolutist ideas of Hobbes. His Essay on Civil Government was published in 1690, less than two years after the second British revolution of 1688. It is understandable that, writing soon after an event of such importance, a political writer should find it necessary to take a position and to make known his opinion about this matter. Locke justified the revolution.
The Essay on Civil Government (Two Treatises of Government, by John Locke) is divided in two parts. In the first one he takes the trouble to refute Filmer. In the second, starting from Hobbes hypothesis, which admits a natural state followed by a social pact (a common idea of various writers of the XVII and XVIII centuries), Locke arrives at conclusions opposed to those supported by Hobbes. (…)
It is to Locke that we owe the almost complete elaboration of the theory of the three fundamental powers, later on developed by Montesquieu.” (G. Mosca e G. Bouthoul, História das Doutrinas Políticas, pp. 191-192; emphasis added. Quoted in Arnaldo Sisson Filho. What Is Wrong With Politics? Bases for a True Democracy; chapter 4: Liberalism: Premisses and Political System)