For example, an edict of 8 March 1804 by King Ferdinand VII resolved that no knight of the military orders might wed without having a council vouch for the limpieza de sangre of his spouse. However, laws requiring limpieza de sangre were still sometimes adopted even into the 19th century.
Tests of limpieza de sangre had begun to lose their utility by the 19th century rarely did persons have to endure the grueling inquisitions into distant parentage through birth records. This idea was reinforced by the fact that, as a result of the Reconquista, numerous Spanish noble lineages were already of Basque origin. The universal hidalguía of Basques helped many of them to positions of power in the administration. Because the Umayyad conquest of Hispania had not reached the Basque territories, it was believed that Basques had maintained their original purity, while the rest of Spain was suspect of miscegenation. The claim to universal hidalguía (lowest nobility) of the Basques was justified by intellectuals such as Manuel Larramendi (1690–1766). Upwardly mobile New Christian families had to either contend with discrimination, or bribe officials and falsify documents attesting generations of Christian ancestry.
The religious and military orders, guilds and other organizations incorporated in their by-laws clauses demanding proof of cleanliness of blood. This stratification meant that the Old Christian commoners might assert a right to honor even if they were not in the nobility. Initially, these statutes were condemned by the monarchy and the Church however, in 1496, Pope Alexander VI approved a purity statute for the Hieronymites. The first statute of purity of blood was enacted in Toledo, Spain, 1449, where an anti-converso riot succeeded in gaining a ban on conversos and their descendants from most official positions. The concept of purity of blood came to be focused more on ancestry than on personal religion. A commonly leveled accusation was that the New Christians were false converts, secretly practicing their former religion as Crypto-Jews or Crypto-Muslims. Converts from Judaism were referred to as conversos and converts from Islam were known as Moriscos. Spain's population of 7 million included up to a million recent converts from Islam and 200,000 converts from Judaism, who were collectively referred to as " New Christians". By the end of the Reconquista and the conversion or expulsion of Muslim mudéjars and Sephardi Jews, the populations of Portugal and Spain were all nominally Christian.