Limpieza de sangre (Spanish: [limˈpjeθa ðe ˈsaŋɡɾe]), Limpeza de sangue (Portuguese: [lĩˈpezɐ ðɨ ˈsɐ̃ɡɨ], Galician: [limˈpeθa ðe ˈsaŋɡe]) or Neteja de sang (Catalan: [nəˈtɛʒə ðə ˈsaŋ]), literally "cleanliness of blood" and meaning "blood purity", played an important role in the modern history of the Iberian Peninsula.
It referred to those who were considered pure "Old Christians", without Muslim or Jewish ancestors, or within the context of the empire (New Spain and Portuguese India) usually to those without ancestry from the Indigenous peoples of the Americas, Asia, or Africa.
By the end of the Reconquista and the conversion of Muslim mudéjars and Sephardi Jews, the population of Portugal and Spain was all nominally Christian. Out of Spain's population of 7 million, this included up to a million recent converts from Islam and 200,000 converts from Judaism, who were collectively referred to as "New Christians". Converts from Judaism were referred to as conversos or marranos, and converts from Islam were known as Moriscos. A commonly leveled accusation was that the New Christians were false converts, secretly practicing their former religion as Crypto-Jews or Crypto-Muslims. Nevertheless, the concept of cleanliness of blood came to be more focused on ancestry than of personal religion. The first statute of purity of blood appeared in Toledo, Spain, 1449, where an anti-converso riot succeeded in obtaining a ban on conversos and their posterity from most official positions. Initially, these statutes were condemned by the monarchy and the Church; however, in 1496, Pope Alexander VI approved a purity statute for the Hieronymites.