The slavery of the past few centuries was often based exclusively on skin color. In the United States, many black people were considered slaves because of their nationality; many slave owners truly believed black people to be inferior human beings.
Utumwa wa karne chache zilizopita hasa ulikuwa kwa misingi ya rangi ya ngozi. Marekani, wengi wa watu weusi walichukuliwa kuwa watumwa kwa sababu ya utaifa wao; wamiliki wa wengi wa watumwa kwa kweli waliamini kuwa watu weusi si wanadamu kamili. Bibilia basi inakataa utumwa kwa misingi ya rangi. Uchukulie utumwa Wayahudi walikuwa nao wakati walikuwa Misri. Wayahudi walikuwa watumwa, si kwa kupenda kwao, lakini kwa sababu walikuwa Wayahudi (Kutoka 13:14).