Nicolo Machiavelli, tr. W.K. Mariott, Il Principe courtesy of Project Gutenberg:
Chapter IV Why the Kingdom of Darius, Conquered by Alexander, did not Rebel Against the Successors of Alexander at his Death
Considering the difficulties which men have had to hold to a newly acquired state, some might wonder how, seeing that Alexander the Great became the master of Asia in a few years, and died whilst it was scarcely settled (whence it might appear reasonable that the whole empire would have rebelled), nevertheless his successors maintained themselves, and had to meet no other difficulty than that which arose among themselves from their own ambitions.
I answer that the principalities of which one has record are found to be governed in two different ways; either by a prince, with a body of servants, who assist him to govern the kingdom as ministers by his favour and permission; or by a prince and barons, who hold that dignity by antiquity of blood and not by the grace of the prince. Such barons have states and their own subjects, who recognize them as lords and hold them in natural affection. Those states that are governed by a prince and his servants hold their prince in more consideration, because in all the country there is no one who is recognized as superior to him, and if they yield obedience to another they do it as to a minister and official, and they do not bear him any particular affection.
The examples of these two governments in our time are the Turk and the King of France. The entire monarchy of the Turk is governed by one lord, the others are his servants; and, dividing his kingdom into sanjaks, he sends there different administrators, and shifts and changes them as he chooses. But the King of France is placed in the midst of an ancient body of lords, acknowledged by their own subjects, and beloved by them; they have their own prerogatives, nor can the king take these away except at his peril. Therefore, he who considers both of these states will recognize great difficulties in seizing the state of the Turk, but, once it is conquered, great ease in holding it. The causes of the difficulties in seizing the kingdom of the Turk are that the usurper cannot be called in by the princes of the kingdom, nor can he hope to be assisted in his designs by the revolt of those whom the lord has around him. This arises from the reasons given above; for his ministers, being all slaves and bondmen, can only be corrupted with great difficulty, and one can expect little advantage from them when they have been corrupted, as they cannot carry the people with them, for the reasons assigned. Hence, he who attacks the Turk must bear in mind that he will find him united, and he will have to rely more on his own strength than on the revolt of others; but, if once the Turk has been conquered, and routed in the field in such a way that he cannot replace his armies, there is nothing to fear but the family of this prince, and, this being exterminated, there remains no one to fear, the others having no credit with the people; and as the conqueror did not rely on them before his victory, so he ought not to fear them after it.
The contrary happens in kingdoms governed like that of France, because one can easily enter there by gaining over some baron of the kingdom, for one always finds malcontents and such as desire a change. Such men, for the reasons given, can open the way into the state and render the victory easy; but if you wish to hold it afterwards, you meet with infinite difficulties, both from those who have assisted you and from those you have crushed. Nor is it enough for you to have exterminated the family of the prince, because the lords that remain make themselves the heads of fresh movements against you, and as you are unable either to satisfy or exterminate them, that state is lost whenever time brings the opportunity.
Now if you will consider what was the nature of the government of Darius, you will find it similar to the kingdom of the Turk, and therefore it was only necessary for Alexander, first to overthrow him in the field, and then to take the country from him. After which victory, Darius being killed, the state remained secure to Alexander, for the above reasons. And if his successors had been united they would have enjoyed it securely and at their ease, for there were no tumults raised in the kingdom except those they provoked themselves.
But it is impossible to hold with such tranquillity states constituted like that of France. Hence arose those frequent rebellions against the Romans in Spain, France, and Greece, owing to the many principalities there were in these states, of which, as long as the memory of them endured, the Romans always held an insecure possession; but with the power and long continuance of the empire the memory of them passed away, and the Romans then became secure possessors. And when fighting afterwards amongst themselves, each one was able to attach to himself his own parts of the country, according to the authority he had assumed there; and the family of the former lord being exterminated, none other than the Romans were acknowledged.
When these things are remembered no one will marvel at the ease with which Alexander held the Empire of Asia, or at the difficulties which others have had to keep an acquisition, such as Pyrrhus and many more; this is not occasioned by the little or abundance of ability in the conqueror, but by the want of uniformity in the subject state.
Gloss: Specialists in the sixteenth century tell us that Machiavelli wrote to shape the future not describe the past, in a time when northern Italians had just begun to study Greek after a thousand-year hiatus and when each historian needed to invent his own methodology. Nevertheless, I think that he has a point. An authoritarian state can be conquered in a brief time, because the institutions of control already exist and it is merely necessary to put new men in charge of them, whereas persuading a mass of tiny polities to acknowledge outside authority can take centuries. When Alexander reached Bactria, he appointed new officials and life went on as it had before with clerks writing “year X of Alexander the ruler” instead of “year X of Darius the ruler.” For any army, however skillful, and any general, however bold and lucky, to conquer from the Aegean to India in ten years required that the space between already be organized into one or a handful of states. For the same reason, since Cyrus the Great gained control of Iran in a few years, we can assume that it was at least as politically centralized as Caesar’s Gaul.
Achaemenid historians still debate whether the kings were all-powerful and able to make and break satraps as they chose, or figureheads with limited power over their provincial governors. While the Achaemenid empire and the Ottoman empire ruled similar territories, that does not mean that they have anything else in common.
Further Reading: Ada Palmer’s essays on Machiavelli.