Equality has been seen as the core of any quest of justice since Aristotle's Nicomachian Ethics. Reaching not only situational equality, but equality in status, however, had not been achieved until modern times. The father of ethics and his systematic enquiry into the concept of justice did not have any problems with foreigners without rights, women as second-class citizens and enslaving people - nor did antiquity at large, medieval era or even the high renaissance. While suum cuique (treating equal issues equally and unequal issues unequally) had been in place since antiquity and Cicero, personal status still had to wait to be recognised as a target of equality concerns. Related to this, no agenda was designed for achieving a paradigm reaching beyond mere formal equality, which only implies treating same things formally the same, and the material quest for equality has come to the fore as a vision only very recently. This book explores these issues - from general equality to equality also in personal status, hence also anti-discrimination, and the change from formal to material concepts of equality - in time and in theoretical approaches. In time, it describes firstly how the equality of indigenous people in Latin America was originally developed as a postulate on the basis of the Bible (all men are similar to God) and from that also as a postulate of equality in law.