Proslavery Cartoon, 1850 “Slavery as it exists in America. Slavery as it exists in England,” 1850, via Library Company of Philadelphia. European alliances helped the American antislavery movement. But proslavery supporters also drew transatlantic comparisons. This proslavery image ignorantly portrays enslaved people who, according to white observers, were cheerful and pleased with their bondage. Proslavery advocates attempted to claim that English factory workers suffered a worse “slavery” than enslaved Africans and African Americans in the American South.