What assyria build an empire in mesopotamia?

Assyria was able to build a vast empire in Mesopotamia because of its military power and well-organized government.  Also, there was a substantial population in Mesopotamia who could be harnessed both for their agricultural ability and also be draft as soldiers in the Assyrian Army.

montesquieu took the view that the roman republic had powers separated so that no one could usurp complete power. in the british constitutional system, montesquieu discerned a separation of powers among the monarch, parliament, and the courts of law.

this is a good question! i'll do some research and come back when i have the answer!