"Cleaning the blood" and "caste" in Spain and its colonies Main article: Statutes of limpieza caste system based on the doctrine of "purity of blood", imposed by Spain in America, established differences in social roles guaranteeing the supremacy of the aristocracy. The doctrine of purity of blood, was a system of discrimination based on arguments from Catholic theology and Aristotle's thought, which appeared in the fourteenth century in Spain in the modern age. The system established a differentiation between persons of blood "pure" and people who were "castes" or "cross" (mestizos, mulattoes, thoroughbred, etc.), Which were believed to have the blood "impure" or "dirty" . On this basis, created a stratified society. The doctrine of purity of blood was used initially to persecute the Jews and then to segregate the Spanish who wanted to settle in America, as well as Indians and blacks and their descendants.After the order of expulsion of Sephardic Jews, many Jews converted to Catholicism to enjoy the same rights as Christians. It was then came the "statutes of purity of blood", that established the "research" genealogy of the people, with claims of privilege, in order to determine whether they had "blood" Jewish, "arrears" or heretic, preventing in these cases the income to schools, military locations, monasteries, chapters and the Inquisition.In this sense it is said that for the first time in history, used the concepts of "race" and "blood" as a strategy of exclusion, researchers disagree about the fact that a connection between the medieval notions " race "and" blood ", including the Old Christians, with the contemporary meaning of these terms. The doctrine of purity of blood, was also applied by the Spanish Empire in America as justification for domination of the Spanish on the ancient Indian civilizations, as well as residents who have indigenous or African ancestry. In the Spanish colonies in America, established a social stratification system roles and privileges established between people. The Spanish Empire believed that among humans some people belonging to "pure breed" (whites, Indians and blacks) and others were "castes" or "cross" as a result of sexual relations between people of different "pure races."The colonial regime sought to prevent racial mixing, not assigning value to the people who were "crossing," purebred. Within the "pure breeds", the "white race" was superior to the "indigenous race" and this in turn was higher than the "black." Within the "pure races" had also distinctions, recognizing the Spanish peninsular (born in Spain) privileges on the Spanish Americans or Creoles (children of Spanish-born mother and father in America). Similarly, the black man born in Africa had less rights than American-born black. Brad Powers For people who were "cross" or "caste" was established a detailed classification, allocation of roles, rights and obligations created by specific names for each "cross" "mestizo," "mulatto," "cunning," "Sambo "cholo," "quadroon," "Chinese", "jump back", "Tent in the air", etc..Thus, for example, punishment for the same crime varied by race or caste to which he belonged. The Peruvian historian Alberto Flores Galindo, with his work Looking for an Inca: Identity and Utopia in the Andes, was one of the first to reveal the processes of racism in Latin America and its roots in the colonial order, particularly in Peru . YH Yerushalmi has pointed out that the ideology of purity of blood is the first history of modern racism, using the term "protorracismo." For his part, Cecil Roth "doctrine compared with the racial anti-Semitism of the Nazi regime," assimilating, and then withdraw because of the differences between "racial anti-Semitism" Spanish described by Roth and the "Nazi anti-Semitism." Max Torres Sebastian Hering published in 2006 in German, the book Rassismus in der Vormoderne. Die 'Reinheit des bluten' in Spanien der Fr her Neuzeit (Racism in the pre-modern.The purity of blood in Spain in the early Middle Ages), which examines the persecution of the Jews in Spain by the principle of cleaning blood from 1391-1674."Hering concluded that the cleaning system of blood can be described as" racial anti-Semitism 'is racist because it plays a role similar to modern marginalization and anti-Jewish because its theological foundations Aristotelian belongs to a tradition prior to the Modern Age " . Zandra Pedraza Gomez highlights the fact that Hering did not analyze "the practice and the representation of this ideology in the Spanish colonies, where the purity of blood along with other early anthropological arguments were used to judge the differences of indigenous groups , order their indoctrination, have their labor and the growing population control mestizo and Creole ", proposing the need for further study in this sense because of the role played by racism in the emergence of a capitalist world system colonialist. In the Spanish colonies in America, mestizaje was a paradoxical process, while banned mass.