After a lengthy introduction, Facundo's fifteen chapters divide broadly into three sections: chapters one to four outline Argentine geography, anthropology, and history; chapters five to fourteen recount the life of Juan Facundo Quiroga; and the concluding chapter expounds Sarmiento's vision of a future for Argentina under a Unitarist government. In Sarmiento's words, the reason why he chose to provide Argentine context and use Facundo Quiroga to condemn Rosas's dictatorship is that "in Facundo Quiroga I do not only see simply a caudillo, but rather a manifestation of Argentine life as it has been made by colonization and the peculiarities of the land".
Facundo begins with a geographical description of Argentina, from the Andes in the west to the eastern Atlantic coast, where two main river systems converge at the boundary between Argentina and Uruguay. This river estuary, called the Rio de Plata, is the location of Buenos Aires, the capital. Through his discussion of Argentina's geography, Sarmiento demonstrates Buenos Aires' advantages; the river systems were communications arteries which, by enabling trade, helped the city to achieve civilization. Buenos Aires failed to spread civilization to the rural areas and as a result, much of the rest of Argentina was doomed to barbarism. Sarmiento also argues that the pampas, Argentina’s wide and empty plains, provided "no place for people to escape and hide for defense and this prohibits civilization in most parts of Argentina". Despite the barriers to civilization caused by Argentina’s geography, Sarmiento argues that many of the country's problems were caused by gauchos like Juan Manuel de Rosas, who were barbaric, uneducated, ignorant, and arrogant; their character prevented Argentine society's progress toward civilization. Sarmiento then describes the four main types of gaucho and these characterizations aid in understanding Argentine leaders, such as Juan Manuel de Rosas. Sarmiento argues that without an understanding of these Argentine character types, "it is impossible to understand our political personages, or the primordial, American character of the bloody struggle that tears apart the Argentine Republic".
Sarmiento then moves on to the Argentine peasants, who are "independent of all need, free of all subjection, with no idea of government". The peasants gather at taverns, where they spend their time drinking and gambling. They display their eagerness to prove their physical strength with horsemanship and knife fights. Rarely these displays led to deaths, and Sarmiento notes that Rosas's residence was sometimes used as a refuge on such occasions, before he became politically powerful.
According to Sarmiento, these elements are crucial to an understanding of the Argentine Revolution, in which Argentina gained independence from Spain. Although Argentina’s war of independence was prompted by the influence of European ideas, Buenos Aires was the only city that could achieve civilization. Rural people participated in the war to demonstrate their physical strengths rather than because they wanted to civilize the country. In the end, the revolution was a failure because the barbaric instincts of the rural population led to the loss and dishonor of the civilized city—Buenos Aires.
Life of Juan Facundo Quiroga
The second section of Facundo explores the life of its titular character, Juan Facundo Quiroga—the "Tiger of the Plains". Despite being born into a wealthy family, Facundo received only a basic education in reading and writing. He loved gambling, being called el jugador (the player)—in fact, Sarmiento describes his gambling as "an ardent passion burning in his belly". As a youth Facundo was antisocial and rebellious, refusing to mix with other children, and these traits became more pronounced as he matured. Sarmiento describes an incident in which Facundo killed a man, writing that this type of behaviour "marked his passage through the world". Sarmiento gives a physical description of the man he considers to personify the caudillo: "[he had a] short and well built stature; his broad shoulders supported, on a short neck, a well-formed head covered with very thick, black and curly hair", with "eyes ... full of fire".
Facundo's relations with his family eventually broke down, and, taking on the life of a gaucho, he joined the caudillos in the province of Entre Ríos. His killing of two Spaniards after a jailbreak saw him acclaimed as a hero among the gauchos, and on relocating to La Rioja, Facundo was appointed to a leadership position in the Llanos Militia. He built his reputation and won his comrades' respect through his fierce battlefield performances, but hated and tried to destroy those who differed from him by being civilized and well-educated.
In 1825, when Unitarist Bernardino Rivadavia became the governor of the Buenos Aires province, he held a meeting with representatives from all provinces in Argentina. Facundo was present as the governor of La Rioja. Rivadavia was soon overthrown, and Manuel Dorrego became the new governor. Sarmiento contends that Dorrego, a Federalist, was interested neither in social progress nor in ending barbaric behaviour in Argentina by improving the level of civilization and education of its rural inhabitants. In the turmoil that characterized Argentine politics at the time, Dorrego was assassinated by Unitarists and Facundo was defeated by Unitarist General José María Paz. Facundo escaped to Buenos Aires and joined the Federalist government of Juan Manuel de Rosas. During the ensuing civil war between the two ideologies, Facundo conquered the provinces of San Luis, Cordoba and Mendoza.
On return to his San Juan home, which Sarmiento says Facundo governed "solely with his terrifying name", he realized that his government lacked support from Rosas. He went to Buenos Aires to confront Rosas, who sent him on another political mission. On his way back, Facundo was shot and killed at Barranca Yaco, Córdoba. According to Sarmiento, the murder was plotted by Rosas: "An impartial history still awaits facts and revelations, in order to point its finger at the instigator of the assassins".
Consequences of Facundo's death
In the book's final chapters, Sarmiento explores the consequences of Facundo's death for the history and politics of the Argentine Republic. He further analyzes Rosas's government and personality, commenting on dictatorship, tyranny, the role of popular support, and the use of force to maintain order. Sarmiento criticizes Rosas by using the words of the dictator, making sarcastic remarks about Rosas's actions, and describing the "terror" established during the dictatorship, the contradictions of the government, and the situation in the provinces that were ruled by Facundo. Sarmiento writes, "The red ribbon is a materialization of the terror that accompanies you everywhere, in the streets, in the bosom of the family; it must be thought about when dressing, when undressing, and ideas are always engraved upon us by association".
Finally, Sarmiento examines the legacy of Rosas's government by attacking the dictator and widening the civilization–barbarism dichotomy. By setting France against Argentina—representing civilization and barbarism respectively—Sarmiento contrasts culture and savagery:
France's blockade had lasted for two years, and the 'American' government, inspired by 'American' spirit, was facing off with France, European principles, European pretensions. The social results of the French blockade, however, had been fruitful for the Argentine Republic, and served to demonstrate in all their nakedness the current state of mind and the new elements of struggle, which were to ignite a fierce war that can end only with the fall of that monstrous government.