The abolition of slavery in Spain began in 1820 with the abolition of the slave trade under pressure from Great Britain, although illegal clandestine trade continued with the support of governments and the crown. The definitive abolition of slavery in the Spanish colonial empire came sixty years later. Although the First Spanish Republic approved the abolition of slavery in Puerto Rico, it was not until 1886 that the Liberal government of Práxedes Mateo Sagasta ended the "patronato" system for freed slaves in Cuba, implementing a law passed in 1880 under the Conservative government of Antonio Cánovas del Castillo. As Eduardo Galván Rodríguez has noted, "Spain was the last Western power to abolish slavery."
Background
During the , , and centuries, few authors opposed slavery, while works justifying and legitimizing it, particularly regarding barbarians, infidels, and Black people, were abundant. "Slavery is considered an accepted and sanctioned social practice by laws and Christian doctrine, from the Bible to Saint Paul and Saint Thomas," noted José Antonio Piqueras. "In America, it was common among wealthy men and women and even among ordinary people if they could afford it. In the Peninsula, the nobility and clergy owned slaves," Piqueras added.
In the first half of the century, the Dominican friar Bartolomé de las Casas denounced the enslavement of indigenous people and sent numerous writings to King Charles of Habsburg to end it, achieving success in 1542 with the approval of the New Laws. As an alternative, Las Casas advocated bringing Black slaves to America to perform the hardest tasks previously done by indigenous people. However, in the last third of his life, he regretted this and also condemned the slavery of Black people as "equally unjust as that of the indigenous". His change of stance was reportedly triggered by a 1547 visit to Lisbon—then Europe’s main slave-trading port—where Portuguese Dominicans informed him about the brutal capture of Black slaves on African coasts and provided books on Portuguese conquests in Africa and Asia. The case of the freed Black man Pedro Carmona from Puerto Rico, who was re-enslaved along with his wife and whom Las Casas helped file an appeal with the Council of the Indies around the same time—paying the bail to free him from prison after being declared a "fugitive slave"—also influenced him.
However, unlike his denunciation of indigenous slavery, Las Casas’ defense of Black slaves "did not gain much traction", as Magdalena Díaz Hernández noted, primarily because his History of the Indies (completed between 1555 and 1561), which dedicated six chapters to the issue, was not published until 1875 due to an explicit ban by King Philip II, Charles’ son and successor, on printing any book related to the Indies under severe penalties, including death. In those six chapters, Las Casas refutes the idea that Black people captured in Africa were enslaved as a result of a "just war," arguing instead that what occurred were "cruel wars, massacres, captivities, total destruction, and annihilation of many peaceful and secure peoples... who never opposed, harmed, waged war, or obstructed the faith, nor ever thought to impede it."
Since Las Casas’ History of the Indies was not published until 1875, the Arte de los contratos by , published in 1573, is often considered the first work to challenge the slave trade, deeming the capture and purchase of Africans contrary to natural law and describing their trade as "butchery". However, the book was banned by the Spanish Inquisition. Two years later, Tomás de Mercado published Summa de tratos y contratos, questioning the causes of slavery and criticizing the dramatic conditions of the transport of African slaves to America, which he witnessed firsthand during his years in New Spain. In 1627, the Jesuit Alonso de Sandoval also denounced the slave trade in his De instauranda Æthiopum salute.
The first to clearly reject slavery—and the associated trade—were two Capuchin friars, and , who met in Havana and were expelled in 1682 for preaching the freedom of Black slaves. Francisco José de Jaca wrote Resolución sobre la libertad, delegitimizing slavery because humans were free by nature. Moirans wrote Servi liberi, similarly defending the freedom of slaves, stating, "All men are free." Both were deported and brought before the Council of the Indies, which barred them from returning to America. They ended their days in Rome.
José Antonio Piqueras has highlighted "the near absence of anti-slavery thought in Spain between the and centuries," contrasting with other European countries where works challenging slavery and the Atlantic slave trade proliferated, especially from the second half of the century. Piqueras attributes this to Spain’s creation of "perfect conditions for intolerance of difference" and the formation of "a social hierarchy that found the slavery of those of ‘infamous’ origin natural."
Cortes of Cádiz (1810–1814): First (failed) abolition attempt
Some liberal deputies of the Cortes of Cádiz spoke out against the African slave trade, shortly after the United Kingdom abolished the slave trade in the British Empire in 1807. The most immediate Spanish precedent available to the deputies was the Dissertation against "ignominious slavery" and the slave trade, the "infamous system", presented by the enlightened at the Madrid Academy of Law in 1802, five years before Britain’s ban, making him a pioneer of European and global abolitionism. The full title of the Dissertation was Dissertation on the origin of Black slavery, the reasons for its perpetuation, the advantages attributed to it, and the means that could be adopted to make our colonies prosper without it. However, the Dissertation was not published until July 1811, shortly after the April debate in the Cortes of Cádiz on the abolition of slavery. In the Dissertation, Antillón argued that the trade and slavery of Black people, "infamous, a stain and blemish on European culture," "dishonors the philosopher and shames enlightened governments".
On April 2, 1811, the Cortes of Cádiz debated two proposals: one for the gradual abolition of slavery, as it was "contrary to natural law," presented by the New Spain deputy José Miguel Guridi y Alcocer, and another by Agustín Argüelles, leader of the liberals, to ban the "infamous" slave trade, following Britain’s example, then an ally of the "patriots" in the Spanish War of Independence. The latter did not include abolishing slavery itself, as Argüelles believed it was not the time to debate it due to the "issue... requiring the utmost caution, given the painful example in Santo Domingo," referring to the Haitian Revolution that began in 1791. Guridi y Alcocer’s proposal, which also included ending the slave trade, "envisioned declaring free the [slaves] born henceforth from enslaved women (known as free womb), abolishing physical punishments, paying a small wage to slaves remaining in captivity, and recognizing their right to coartation [self-purchase] at the price they were acquired. This abolitionist plan, for gradual extinction, would take 60 to 70 years to be fully recognized."
The debate caused great alarm in Cuba, and the Captain General of the island and the Council of Havana sent representations to the Cortes expressing strong opposition to both proposals—the Havana council’s was drafted by deputy Francisco de Arango y Parreño, born in the Cuban capital. Regarding the suppression of the slave trade, Arango argued it would lead Cuba to poverty, as no estate had sufficient Black slaves, and "very few have females". The Cuban pressure was effective—supported by absolutist deputies and some liberals—and neither issue was discussed again in the Cortes, only mentioned tangentially, with the commission meant to address them never formed.
The Spanish Constitution of 1812 enshrined the existence of slavery. Article 3.1 stated that "Spaniards are all free men born and residing in the domains of Spain," implicitly recognizing the existence of non-free men and women. Article 18 established that "citizens are those Spaniards who, on both sides, trace their origin to the Spanish domains in both hemispheres," a formula excluding those of African origin—"simply because they were descendants of slaves while slavery remained in force", as José Antonio Piqueras noted. Article 22 opened "the door of virtue and merit to become citizens" for "Spaniards who by any line are considered and reputed to be of African origin." It continued: "consequently, the Cortes will grant a citizen’s letter to those who render qualified services to the homeland or distinguish themselves by talent, diligence, and conduct, provided they are born of a legitimate marriage to free parents, married to a free woman, and residing in the domains of Spain, and exercise a profession, trade, or useful industry with their own capital." This article has been described by José Antonio Piqueras as a "miserable gesture of condescension".
From his exile in England, the liberal José María Blanco White—who had coincided with Antillón in Seville and frequently addressed slavery in (1810–1814), reproducing some parliamentary speeches by the British abolitionist William Wilberforce—published in London in 1814 Bosquejo del comercio de esclavos y reflexiones sobre el tráfico considerado moral, política y cristianamente, a work "whose importance is equal to or greater than Antillón’s Dissertation," according to . In it, Blanco White defended—against the "shameful capitulation" of the liberals in the Cortes of Cádiz— the abolition of the slave trade and slavery, though he was cautious about implementation, warning that "if all [slaves] were freed at once," there was a risk "they might turn to disorder instead of freedom, to pillage instead of industry", leading to the "ruin of a large portion of owners, resulting in desolation and universal upheaval". Blanco White highlighted the double standard of those who opposed torture "while considering it a most difficult problem to decide whether we have the right to torment an unlimited number of ‘innocents’."
Reigns of Ferdinand VII and Isabella II (1814–1868): Abolition in the Peninsula and the "Golden Age" of the "Illegal" Slave Trade Evidence of changing European perceptions of the slave trade after the Napoleonic Wars was the Declaration of the Powers on the Slave Trade of February 8, 1815, from the Congress of Vienna, signed by absolutist monarchies and the British monarchy—which proposed the declaration against the "infamous trade" it had banned in 1807. Following the declaration, the United Kingdom pressured other European monarchies to abolish the slave trade in their domains. A primary target was the monarchy of Ferdinand VII, who signed a treaty with Britain on September 23, 1817, abolishing the slave trade in the Spanish Empire in exchange for £400,000. The first article of the treaty stated:
Francisco Arango—who remained in Spain and was appointed by Ferdinand VII to the Council of the Indies—secured a delay in the treaty’s enforcement until 1820. In a plea to the king, endorsed by six other councilors, he argued that "under no circumstances can we agree to an immediate ban on the slave trade" because "the American provinces, in the sad necessity of cultivating their lands with slaves, have no means to replace those who die or are [hanged]," noting that in none of "the estates in America... is the number of females proportionate to males." Thus, "it would abruptly close all sources of prosperity". He also used a blatantly racist argument: "We worry about barbarians without order or civilization who have never used their freedom except to sell or devour each other." In 1834, Arango was awarded the title of by the regent Maria Christina, who, along with her second husband Agustín Fernando Muñoz, profited from the slave trade and a Cuban sugar plantation worked by slaves.