In many slave societies manumission coexisted with perpetual bondage, often featured by self-purchase by slave artisans, a practice that some societies monitored through recognition of the slave's legal personality as a contracting party. Manumission played a comparatively minor role in shaping North American slavery, with debatable exceptions in the mid-Atlantic region; historians of slavery there have portrayed manumitters as individuals of conscience and/or economic maximizers seeking profitable exits from a locally declining labor institution. This contrast was first noted by Frank Tannenbaum, who characterized slavery in Spanish- and Portuguese-speaking America as milder than in British America, and targeted differences in religion and in the European history of slavery of each society as key explanatory factors.
Ring Shout, Wheel About: The Racial Politics of Music and Dance in North American Slavery