在美國獨立之前，非洲黑奴已廣佈於各大殖民地。對當時多數的白人而言，奴隸的存在雖有其可議之處，但此制度自古有之，此外，社會中存在領導與被領導階層是自然現象，不同人種與社會背景之人分屬社會不同階級亦屬平常，這是人類社會發展過程中的「必要之惡」（necessary evil），是正常現象，不足為奇。1776 年的美國獨立革命，除了刺激部份美國民眾開始對奴隸制度進行反思外，隨著反奴言論在北方逐漸匯集成一股運動，相關捍衛奴隸制度的論述，也在南方社會隨之而起，並與北方反奴運動形成相抗衡之勢。自19 世紀初至1860 年為止，美國南方已建立一套涵蓋政治、社會、經濟、宗教以及人種等各層面，解釋奴隸制度正當性的具體論述與思辨邏輯，強調奴隸制度在美國南方有其存在價值與必要性，奴隸制度並非罪惡，它對美國南方甚至全國的發展，是「全然有益」（positive good）之事。

Black Slaves were distributed among the 13 colonies. During the colonial
period, people believed that slavery was an evil, but it was necessary, since the institution was an integral part of the society and life of the colonies and played a pivotal role of the British Empire. Basically, there were no serious threats to slavery during the colonial era. However, the American Revolution set the stage for attacks on slavery and aroused a strong defense of slavery in turn. From the Revolution to
the Civil War, Southerners developed a variety of defense of slavery from different aspects of theology, history, social and political theories, economy, and science,arguing that slavery was a “positive good,” the indispensable cornerstone of southern society. Such transformation of southerners’ thinking about slavery from “necessary evil” to “positive good” was indeed one of the crucial roots of the Civil War.