Slavery helped finance the Industrial Revolution in England. Plantation owners, shipbuilders, and merchants connected with the slave trade accumulated vast fortunes that established banks and heavy industry in Europe and expanded the reach of capitalism worldwide. Eric Williams advanced these powerful ideas in the influential and widely debated Capitalism and Slavery, published in 1944 and based on his previously unavailable dissertation, now available in book form for the first time. Williams’s profound critique became the foundation for studies of imperialism and economic development. Establishing the exploitation of commercial capitalism and its link to racial attitudes, Williams employed a historicist vision that has set the tone for an entire field. The significant differences between his two works allows us to reconsider questions that have lost none of their urgency; indeed, whose importance has increased.