Nearly all historical laws concerning marriage and "race" or caste had the same objective: to preserve the purity of the dominant group by preventing mixing with groups considered inferior. From the Roman Twelve Tables, which forbade marriages between patricians and plebeians, to the statutes of blood purity in the Hispanic world and the caste system in the Indies, the pattern repeated itself. Independent Paraguay, however, produced a notable exception.
Following the May Revolution of 1811, the newly formed Consular Government faced the persistent influence of European Spaniards, who maintained economic power and a dense network of family alliances with the main Creole houses. To combat this influence, on March 1, 1814, one of the harshest measures of the period was decreed: the prohibition of marriages between European Spanish men and American women considered "Spanish."
Herein lies the singular inversion: instead of prohibiting mixing to preserve the elite, the decree aimed to extinguish the peninsular elite by forcing them into exogamy or non-reproduction. The calculation was twofold: politically, it deprived the Europeans of their primary mechanism for social reproduction, kinship; fiscally, it ensured that the assets of Spaniards who died without legitimate descendants would go entirely to the public treasury.
The prohibition was specifically written regarding the European man as the active subject. Peninsular Spanish women were not mentioned, which suggests that, in theory, they could marry American men without violating the norm. This silence likely reflected the demographic reality: the presence of peninsular women in Paraguay at the time was minimal compared to that of men.
The Swiss physician Johann Rudolph Rengger, who lived in Asunción between 1819 and 1825 and was personally affected by the law, offered crucial insights. He observed that the category of "European" was in practice expanded to include Rio de la Plata natives from Entre Ríos, Santa Fe, and Buenos Aires, turning the norm also into an instrument against the political influence of the Río de la Plata provinces.
Rengger also argued that the decree, by targeting only legitimate unions, did not suppress relationships but rather increased licentiousness in informal unions. The rigor of its enforcement was evident in cases like that of the Spaniard Juan Bautista Carísimo, who was imprisoned and fined for marrying a white woman, with his assets confiscated.
The punitive use of the legislation reached its extreme with the Zavala and Machaín families, who were said to have had disagreements with the dictator Francia himself. Historiographical tradition recounts that he had both families officially declared "mulatto" and, by a decree in 1835, prohibited the marriage of their descendants up to the fifth generation.
The final effect of the 1814 law was, to a large extent, contrary to the morality it invoked. By not suppressing relationships, but only formal marriage, it ended up fostering an increase in concubinage, an unintended consequence of a measure that sought, above all, political and social control.