India’s social organization shared certain broad features with that of China. In both civilizations, birth determined social status for most people; little social mobility was available for the vast majority; sharp distinctions and great inequalities characterized social life; and religious or cultural traditions defined these inequalities as natural, eternal, and ordained by the gods. Despite these similarities, the organization, flavor, and texture of ancient Indian society were distinctive compared to almost all other civilizations. These unique aspects of Indian society have long been embodied in what we now call the caste system, a term that comes from the Portuguese word casta, which means “race” or “purity of blood.” That social organization emerged over thousands of years and in some respects has endured into modern times.