Under the regime of President Rafael Trujillo, the Dominican Republic witnessed a harsh campaign against Haitians in October 1937. This act, often referred to as the Parsley Massacre, was fueled by Trujillo's desire to assert national identity and restrict the influence of Haiti in the Dominican Republic. Discriminatory sentiments against Haitians were prevalent, largely due to long-standing political tensions and cultural differences, which Trujillo exploited to solidify his power and distract from domestic issues. The killings were characterized by their brutality, with Dominican soldiers and civilians taking part in the violence, often carrying out summary executions. The order aimed at anyone perceived as Haitian, regardless of citizenship or status, further leading to a pervasive climate of fear among border communities. The campaign saw a grim efficiency, marking a dark chapter in Dominican-Haitian relations.

The massacre lasted several days, where witnesses reported soldiers asking individuals to pronounce the word “perejil” (parsley in Spanish) as a means of identifying Haitians, who often struggled to pronounce the Spanish language correctly. This chilling method of identification resulted in widespread killings, with estimates of the death toll ranging from several thousand to tens of thousands. It was also a significant moment of state-sponsored violence, symbolizing the lengths to which Trujillo would go to enforce his vision of a racially homogenous nation. The event showcased not only the brutal nature of his regime but also left lasting scars on Dominican-Haitian relations, shaping the narrative between the two nations for decades.