Montesquieu was fascinated by the liberty which was enjoyed in England, which he attributed to security of person and the rule of law (1748)

Found in Complete Works, vol. 1 The Spirit of Laws

Montesquieu was fascinated by the liberty which was enjoyed in England, which he attributed to the sharp separation of political powers:

The political liberty of the subject is a tranquillity of mind arising from the opinion each person has of his safety. In order to have this liberty, it is requisite the government be so constituted as one man need not be afraid of another.

When the legislative and executive powers are united in the same person, or in the same body of magistrates, there can be no liberty; because apprehensions may arise, lest the same monarch or senate should enact tyrannical laws, to execute them in a tyrannical manner.

For many 18th century Europeans there were two end points on the spectrum concerning liberty. On the far end was Turkey which embodied all that was bad about “oriental despotism”. Voltaire’s Philosophical Dictionary is full of references to the evils of the Turkish model. At the other end of the spectrum was the English constitution which was seen as the embodiment of measured and balanced government under which individuals could flourish. Things began to change after the American Revolution. European classical liberals were now torn between the American “republican” model of liberty and the British “constitutional monarchist” model.