His experience had shown him how weak were the ties which had hitherto been thought sufficient to hold the Empire together, and how slight an obstacle they opposed to the tendency, which all great empires have, to disruption.

But, however natural it might be to desire a remedy for the evils which afflicted the State, it was not easy to devise one.
Great empires had existed in Western Asia for above seven hundred years, and had all suffered more or less from the same inherent weakness; but no one had as yet invented a cure, or even (so far as appears) conceived the idea of improving on the rude system of imperial sway which the first conqueror had instituted.

It remained for Darius, not only to desire, but to design--not only to design, but to bring into action--an entirely new form and type of government.

He has been well called "the true founder of the Persian state." He found the Empire a crude and heterogeneous mass of ill-assorted elements, hanging loosely together by the single tie of subjection to a common head; he left it a compact and regularly organized body, united on a single well-ordered system, permanently established everywhere.
On the nature and details of this system it will be necessary to speak at some length.

It was the first, and probably the best, instance of that form of government which, taking its name from the Persian word for provincial ruler, is known generally as the system of "satrapial" administration.