The answer is probably twofold. First, on the plane of administration, the city organization provided a means of efficiently running large areas of their kingdoms, a task which their own centralized and cumbersome state apparatus could not cope with.

• 可能具有双重原因：其一，从管理层面上讲，城市提供了管理庞大王国的有效办法，这是臃肿的中央集权统治机构无法做到的。