His extensive writings, the most famous being A Short Account of the Destruction of the Indies and Historia de Las Indias, chronicle the first decades of colonization of the Caribbean islands.

He was appointed Bishop of Chiapas, but served only for a short time before he was forced to return to Spain because of resistance to the New Laws by the encomenderos, and conflicts with Spanish settlers because of his pro-Indian policies and activist religious stance.

Las Casas spent 50 years of his life actively fighting slavery and the colonial abuse of Indigenous peoples, especially by trying to convince the Spanish court to adopt a more humane policy of colonization.

"[24] Las Casas and his friend Pedro de la Rentería were awarded a joint encomienda which was rich in gold and slaves, located on the Arimao River close to Cienfuegos.

While waiting, Las Casas produced a report that he presented to the Bishop of Burgos, Juan Rodríguez de Fonseca, and secretary Lope Conchillos, who were functionaries in complete charge of the royal policies regarding the Indies; both were encomenderos.

Las Casas was resolved to see Prince Charles who resided in Flanders, but on his way there he passed Madrid and delivered to the regents a written account of the situation in the Indies and his proposed remedies.

[36] Worried by Las Casas' descriptions of the situation in the Indies, Cardinal Cisneros decided to send a group of Hieronymite monks to take over the government of the islands.

Las Casas worked to recruit a large number of peasants who would want to travel to the islands, where they would be given lands to farm, cash advances, and the tools and resources they needed to establish themselves there.

[41] Following a suggestion by his friend and mentor Pedro de Córdoba, Las Casas petitioned a land grant to be allowed to establish a settlement in northern Venezuela at Cumaná.

Founded in 1515, there was already a small Franciscan monastery in Cumana, and a Dominican one at Chiribichi, but the monks there were being harassed by Spaniards operating slave raids from the nearby Island of Cubagua.

[42] He suggested fortifying the northern coast of Venezuela, establishing ten royal forts to protect the Indians and starting up a system of trade in gold and pearls.

[43] Arriving in Puerto Rico, in January 1521, he received the terrible news that the Dominican convent at Chiribichi had been sacked by Indians, and that the Spaniards of the islands had launched a punitive expedition, led by Gonzalo de Ocampo, into the very heart of the territory that Las Casas wanted to colonize peacefully.

[44] Las Casas worked there in adverse conditions for the following months, being constantly harassed by the Spanish pearl fishers of Cubagua island who traded slaves for alcohol with the natives.

They stayed in the convent founded some years earlier by Fray Domingo Betanzos and studied the Kʼicheʼ language with Bishop Francisco Marroquín, before traveling into the interior region called Tuzulutlan, "The Land of War", in 1537.

It was important for Las Casas that this method be tested without meddling from secular colonists, so he chose a territory in the heart of Guatemala where there were no previous colonies and where the natives were considered fierce and war-like.

Because the land had not been possible to conquer by military means, the governor of Guatemala, Alonso de Maldonado, agreed to sign a contract promising that if the venture was successful he would not establish any new encomiendas in the area.

In Spain, Las Casas started securing official support for the Guatemalan mission, and he managed to get a royal decree forbidding secular intrusion into the Verapaces for the following five years.

He drafted a suggestion for an amendment arguing that the laws against slavery were formulated in such a way that it presupposed that violent conquest would still be carried out, and he encouraged once again beginning a phase of peaceful colonization by peasants instead of soldiers.

[64] As a bishop Las Casas was involved in frequent conflicts with the encomenderos and secular laity of his diocese: among the landowners there was the conquistador Bernal Díaz del Castillo.

It also helped convince more missionaries to come to the Americas to study the indigenous people, such as Bernardino de Sahagún, who learned the native languages to discover more about their cultures and civilizations.

This book, written a decade earlier and sent to the attention of then-prince Philip II of Spain, contained accounts of the abuses committed by some Spaniards against Native Americans during the early stages of colonization.

Las Casas worked hard to convince the emperor that it would be a bad economic decision, that it would return the viceroyalty to the brink of open rebellion, and could result in the Crown losing the colony entirely.

[88] The text, written 1516, starts by describing its purpose: to present "The remedies that seem necessary in order that the evil and harm that exists in the Indies cease, and that God and our Lord the Prince may draw greater benefits than hitherto, and that the republic may be better preserved and consoled.

"[91] He even drew up a budget of each pueblo's expenses to cover wages for administrators, clerics, Bachelors of Latin, doctors, surgeons, pharmacists, advocates, ranchers, miners, muleteers, hospitalers, pig herders, fishermen, etc.

[94] The images described by Las Casas were later depicted by Theodore de Bry in copper plate engravings that served as a medium of the Black Legend against Spain.

"[96] This work in which Las Casas combined his own ethnographic observations with those of other writers, and compared customs and cultures between different peoples, has been characterized as an early beginning of the discipline of anthropology.

[98][99] It was in the History of the Indies that Las Casas finally regretted his advocacy for African slavery, and included a sincere apology, writing: "I soon repented and judged myself guilty of ignorance.

This historiographic phenomenon has been referred to by some historians as the "Black Legend", a tendency by mostly Protestant authors to portray Spanish Catholicism and colonialism in the worst possible light.

Demographic studies such as those of colonial Mexico by Sherburne F. Cook in the mid-20th century suggested that the decline in the first years of the conquest was indeed drastic, ranging between 80 and 90%, due to many different causes but all ultimately traceable to the arrival of the Europeans.

[113] That view is contradicted by Sylvia Wynter, who argued that Las Casas's 1516 Memorial was the direct cause of Charles V granting permission in 1518 to transport the first 4,000 African slaves to Jamaica.