Long after the dust had settled from the Atlantic upheavals, their legacies have continued to provoke controversy. Were these revolutions necessary? Did they really promote the freedoms that they advertised? Did their benefits outweigh their costs in blood and treasure?

To the people who made these revolutions, benefited from them, or subsequently supported them, they represented an opening to new worlds of human possibility, while sweeping away old worlds of oppression, exploitation, and privilege. Modern revolutionaries acted on the basis of Enlightenment ideas, believing that the structure of human societies was not forever ordained by God or tradition and that it was both possible and necessary to reconstruct those societies. They saw themselves as correcting ancient and enduring injustices. To those who complained about the violence of revolutions, supporters pointed to the violence that maintained the status quo and the unwillingness of favored classes to accommodate changes that threatened those unjust privileges. It was persistent injustice that made revolution necessary and perhaps inevitable.

To their victims, critics, and opponents, revolutions appeared in a quite different light. Conservatives generally viewed human societies not as machines whose parts could be easily rearranged but as organisms that evolved slowly. Efforts at radical and sudden change only invited disaster, as the unrestrained violence of the French Revolution at its height demonstrated. The brutality and bitterness of the Haitian Revolution arguably contributed to the unhappy future of that country. Furthermore, critics charged that revolutions were largely unnecessary since societies were in fact changing. France was becoming a modern society, and feudalism was largely gone well before the revolution exploded. Slavery was ended peacefully in many places, and democratic reform proceeded gradually throughout the nineteenth century. Was this not a preferable alternative to revolutionary upheaval?

Historians too struggle with the passions of revolution—both pro and con—as they seek to understand the origins and consequences of these momentous events. Were revolutions the product of misery, injustice, and oppression? Or did they reflect the growing weakness of established authorities, the arrival of new ideas, or the presence of small groups of radical activists able to fan the little fires of ordinary discontent into revolutionary conflagrations? The outcomes of revolutions have been as contentious as their beginnings. Did the American Revolution enable the growth of the United States as an economic and political “great power”? Did the Haitian Revolution stimulate the later end of slavery elsewhere in the Atlantic world? Did the French Revolution and the threat of subsequent revolutions encourage the democratic reforms that followed in the nineteenth century? Such questions have been central to an understanding of the Atlantic revolutions as well as to those that followed in Russia, China, and elsewhere in the twentieth century.