This article traces the association between the European overseas empires and the concept of sovereignty, arguing that, ever since the days of Cicero—if not earlier—Europeans had clung to the idea that there was a close association between a people and the territory it happened to occupy. This made it necessary to think of an “empire” as a unity—an “immense body,” to use Tacitus's phrase—that would embrace all its subjects under a single sovereign. By the end of the eighteenth century it had become possible, in this way, to speak of “empires of liberty” that would operate for the ultimate benefit of all their “citizens,” freeing them from previous tyrannical rulers and bringing them under the protection of more benign regimes. In such empires sovereignty could only ever be, as it had become in Europe, undivided. The collapse of Europe's “first” empires in the Americas, however, was followed rapidly by Napoleon's attempt to create a new kind of Empire in Europe. The ultimate, and costly, failure of this project led many, Benjamin Constant among them, to believe that the age of empires was now over and had been replaced by the age of commerce. But what in fact succeeded Napoleon was the modern European state system, which attempted not to replace empire by trade, as Constant had hoped, but to create a new kind of empire, one that sought to minimize domination and settlement, and to make a sharp distinction between imperial ruler and imperial subject. In this kind of empire, sovereignty could only be “divided.” Various kinds of divided rule were thus devised in the nineteenth century. Far, however, from being an improvement on the past, this ultimately resulted in—or at least contributed greatly to—the emergence of the largely fictional and inevitably unstable societies that after the final collapse of the European empires became the new states of the “developing world.”