The book was written in 1948. The delay in its publication allowed the use of more recent bibliography. The systems of sources for the second and fourth Servile Wars can be found by the Reader in my earlier studies on these topics. The role of the slave movements was not decisive for the history of the Ancient World. The Slaves have the advantage of numbers on their side, but in all other respects, they fall short. They lack the art of war and discipline, nor do they have the political experience of the free. Their origins from various nations, ethnicities, and regions, differences in character, language, beliefs, and goals, the vast distances of those times, and the different conditions of their lives in one place and another, do not allow them to coordinate a general uprising and overwhelm their masters with their mass. Finally, the role of the Landless, who join the Slave Uprisings, is presented only as predatory, and thus, far from helping to establish them, they contribute to their downfall. Thus, in countries where Slavery did not take its worst form, such as in Greece, we do not have serious Slave movements, but sporadic, feeble, and desperate ones. The movement of Aristonicus in the East sweeps the slaves along with it, but it does not rely on them. Major slave wars will break out only in Italy and Sicily, two countries that, with their system of agricultural economy, amass very large slave populations. However, even then, they only break out at critical moments for Rome, when it is entangled in wars or social upheavals, and they are eventually crushed. That the slave movements are crushed is not, however, among the misfortunes of History.