Buenos Aires, officially the Autonomous City of Buenos Aires, is the capital and largest city of Argentina. It is located on the southwest of the Río de la Plata. Buenos Aires is classified as an Alpha− global city, according to the GaWC 2024 ranking. The city proper has a population of 3.1 million and its urban area has a population of 16.7 million, making it the 21st most populous metropolitan area in the world.
It is known for its preserved eclectic European architecture and rich cultural life. It is a multicultural city that is home to multiple ethnic and religious groups, contributing to its culture as well as to the dialect spoken in the city and in other parts of the country. Since the 19th century, the city, and the country in general, has been a major recipient of millions of immigrants from all over the world, making it a melting pot where many ethnic groups live together. Buenos Aires is considered one of the most diverse cities of the Americas.
The city of Buenos Aires is an autonomous district and is neither part of Buenos Aires Province nor its capital. In 1880, after the Argentine Civil War, Buenos Aires was federalized and split from Buenos Aires Province. The city limits were enlarged to include the towns of Belgrano and Flores, both now neighborhoods of the city. The 1994 constitutional amendment granted the city autonomy, hence its formal name of Autonomous City of Buenos Aires. Citizens elected their first chief of government in 1996. Previously, the mayor was directly appointed by the president of Argentina.
The Greater Buenos Aires conurbation includes several surrounding cities, which are located in the neighbouring districts of the Buenos Aires Province. It constitutes the fourth-most populous metropolitan area in the Americas. It is also the second largest city south of the Tropic of Capricorn. Buenos Aires has the highest human development of all Argentine administrative divisions. Its quality of life was ranked 97th in the world in 2024, being one of the best in Latin America.
Etymology
Aragonese archives record that Catalan missionaries and Jesuits arriving in Cagliari (Sardinia) under the Crown of Aragon, after its capture from the Pisans in 1324, established their headquarters on top of a hill that overlooked the city. The hill was known to them as Bonaira (or Bonaria in Sardinian), as it was free of the foul smell prevalent in the old city (the castle area), which was adjacent to swampland. During the siege of Cagliari, the Catalans built a sanctuary to the Virgin Mary on top of the hill. In 1335, King Alfonso the Gentle donated the church to the Mercedarians, who built an abbey that stands to this day. In the years after that, a story circulated, claiming that a statue of the Virgin Mary was retrieved from the sea after it miraculously calmed a storm in the Mediterranean Sea. The statue was placed in the abbey. Spanish sailors, especially Andalusians, venerated this image and frequently invoked the "Fair Winds" to aid them in their navigation and prevent shipwrecks. A sanctuary to the Virgin of the Buen Ayre would later be erected in Seville.
At the foundation of Buenos Aires, Spanish sailors arrived in the Río de la Plata giving thanks to the blessings of Santa Maria de los Buenos Aires, 'Holy Mary of the Good Winds', who they believed to have given them the good winds to reach the coast of what is today the modern city. Pedro de Mendoza called the city 'Holy Mary of the Fair Winds', a name suggested by the chaplain of Mendoza's expedition – a devotee of the Virgin of Buen Ayre – after the Madonna of Bonaria from Sardinia (which is still to this day the patroness of the Mediterranean island). Mendoza's settlement soon came under attack by indigenous people and was abandoned in 1541.
For many years, the name was attributed to a Sancho del Campo, who is said to have exclaimed: "How fair are the winds of this land!" as he arrived. In 1882, after conducting extensive research in Spanish archives, Argentine merchant Eduardo Madero ultimately concluded that the name was instead closely linked with the devotion of the sailors to Our Lady of Buen Ayre. A second (and permanent) settlement was established in 1580 by Juan de Garay, who sailed down the Paraná River from Asunción, now the capital of Paraguay. Garay preserved the name originally chosen by Mendoza, calling the city Ciudad de la Santísima Trinidad y Puerto de Santa María del Buen Aire ('City of the Most Holy Trinity and Port of Saint Mary of the Fair Winds'). The short form that eventually became the city's name, "Buenos Aires", became commonly used during the 17th century.
The usual abbreviation for Buenos Aires in Spanish is Bs.As. It is also common to refer to it as "B.A." or "BA". When referring specifically to the autonomous city, it is very common to colloquially call it "Capital" in Spanish. Since the autonomy obtained in 1994, it has been called "CABA" (per Ciudad Autónoma de Buenos Aires, 'Autonomous City of Buenos Aires').
History
Viceregal times
In 1516, navigator and explorer Juan Díaz de Solís, navigating in the name of Spain, was the first European to reach the Río de la Plata. His expedition was cut short when he was killed during an attack by the native Charrúa tribe in what is now Uruguay. The city of Buenos Aires was first established as Ciudad de Nuestra Señora Santa María del Buen Ayre (literally "City of Our Lady Saint Mary of the Fair Winds") after Our Lady of Bonaria (Patroness Saint of Sardinia) on 2 February 1536 by a Spanish expedition led by Pedro de Mendoza. The settlement founded by Mendoza was located in what is today the San Telmo district of Buenos Aires, south of the city center.
More attacks by the indigenous people forced the settlers away, and in 1542, the site was abandoned. A second (and permanent) settlement was established on 11 June 1580 by Juan de Garay, who arrived by sailing down the Paraná River from Asunción (now the capital of Paraguay). He dubbed the settlement "Santísima Trinidad" and its port became "Puerto de Santa María de los Buenos Aires."
From its earliest days, Buenos Aires depended primarily on trade. During most of the 17th century, Spanish ships were menaced by pirates, so they developed a complex system whereby ships with military protection were dispatched to Central America in a convoy from Seville (the only port allowed to trade with the American colonies) to Lima, Peru, and from there to the other cities of the viceroyalty. Because of this, products took a very long time to arrive in Buenos Aires, and the taxes generated by the transport made them prohibitive. This scheme frustrated the traders of Buenos Aires, and a thriving informal, yet tolerated by the authorities, contraband industry developed inside the viceroyalties and with the Portuguese. This also instilled a deep resentment among porteños towards the Spanish authorities.
Charles III of Spain progressively eased the trade restrictions before finally declaring Buenos Aires an open port in the late 18th century. The capture of Portobelo in Panama by British forces also fueled the need to foster commerce via the Atlantic route, to the detriment of Lima-based trade. One of his rulings was to split a region from the Viceroyalty of Perú and create instead the Viceroyalty of the Río de la Plata, with Buenos Aires as the capital. However, Charles's placating actions did not have the desired effect, and the porteños, some of them versed in the ideology of the French Revolution, instead became even more convinced of the need for independence from Spain.
War of Independence
During the British invasions of the Río de la Plata, British forces attacked Buenos Aires twice. In 1806 the British successfully invaded Buenos Aires, but an army from Montevideo led by Santiago de Liniers defeated them. In the brief period of British rule, the viceroy Rafael Sobremonte managed to escape to Córdoba and designated this city as capital. Buenos Aires became the capital again after its recapture by Argentine forces, but Sobremonte could not resume his duties as viceroy. Santiago de Liniers, chosen as new viceroy, prepared the city against a possible new British attack and repelled a second invasion by Britain in 1807. The militarization generated in society changed the balance of power favorably for the criollos (in contrast to peninsulars), as well as the development of the Peninsular War in Spain.
An attempt by the peninsular merchant Martín de Álzaga to remove Liniers and replace him with a Junta was defeated by the criollo armies. However, by 1810 it would be those same armies who would support a new revolutionary attempt, successfully removing the new viceroy Baltasar Hidalgo de Cisneros. This is known as the May Revolution, which is now celebrated as a national holiday. This event started the Argentine War of Independence, and many armies left Buenos Aires to fight the diverse strongholds of royalist resistance, with varying levels of success. The government was held first by two Juntas of many members, then by two triumvirates, and finally by a unipersonal office, the Supreme Director. Formal independence from Spain was declared in 1816, at the Congress of Tucumán. Buenos Aires managed to endure the whole Spanish American wars of independence without falling again under royalist rule.
Historically, Buenos Aires has been Argentina's main venue of liberal, free-trading, and foreign ideas. In contrast, many of the provinces, especially those to the city's northwest, advocated a more nationalistic and Catholic approach to political and social issues. In fact, much of the internal tension in Argentina's history, starting with the centralist-federalist conflicts of the 19th century, can be traced back to these contrasting views. In the months immediately following said "May Revolution", Buenos Aires sent a number of military envoys to the provinces with the intention of obtaining their approval. Instead, the enterprise fueled tensions between the capital and the provinces; many of these missions ended in violent clashes.
In the 19th century the city was blockaded twice by naval forces: by the French from 1838 to 1840, and later by an Anglo-French expedition from 1845 to 1848. Both blockades failed to bring the Argentine government to the negotiating table, to the frustration of British Parliament in 1847, with the foreign powers eventually desisting from their demands.
19th and 20th centuries
During most of the 19th century, the political status of the city remained a sensitive subject. It was already the capital of Buenos Aires Province, and between 1853 and 1860 it was the capital of the seceded State of Buenos Aires. The issue was fought out more than once on the battlefield, until the matter was finally settled in 1880 when the city was federalized and became the seat of government, with its mayor appointed by the president. The Casa Rosada became the seat of the president.
Health conditions in poor areas were appalling, with high rates of tuberculosis. Contemporaneous public health physicians and politicians typically blamed both the poor themselves and their ramshackle tenement houses (conventillos) for the spread of the dreaded disease. People ignored public-health campaigns to limit the spread of contagious diseases, such as the prohibition of spitting on the streets, the strict guidelines to care for infants and young children, and quarantines that separated families from ill loved ones.
In addition to the wealth generated by customs duties and Argentine foreign trade in general, as well as the existence of fertile pampas, railroad development in the second half of the 19th century increased the economic power of Buenos Aires as raw materials flowed into its factories. In 1888, by Law 2089, the national government of Argentina expanded the City of Buenos Aires by annexing the towns of Belgrano, Flores, and parts of General San Martín Partido, such as today's Villa Devoto. A leading destination for immigrants from Europe, particularly Italy and Spain, from 1880 to 1930, Buenos Aires became a multicultural city that ranked itself alongside the major European capitals. During this time, the Colón Theater became one of the world's top opera venues, and the city became the regional capital of radio, television, cinema, and theater. The city's main avenues were built during those years, and the dawn of the 20th century saw the construction of South America's tallest buildings and its first underground system. A second construction boom, from 1945 to 1980, reshaped downtown and much of the city.
Buenos Aires also attracted migrants from Argentina's provinces and neighboring countries. Shanty towns (villas miseria) started growing around the city's industrial areas during the 1930s, leading to pervasive social problems and social contrasts with the largely upwardly mobile Buenos Aires population. These laborers became the political base of Peronism, which emerged in Buenos Aires during the pivotal demonstration of 17 October 1945, at the Plaza de Mayo. Industrial workers of the Greater Buenos Aires industrial belt have been Peronism's main support base ever since, and Plaza de Mayo became the site for demonstrations and many of the country's political events; on 16 June 1955, however, a splinter faction of the Navy bombed the Plaza de Mayo area, killing 364 civilians (see Bombing of Plaza de Mayo). This was the only time the city was attacked from the air, and the event was followed by a military uprising which deposed President Perón, three months later (see Revolución Libertadora).
In the 1970s the city suffered from the fighting between left-wing revolutionary movements (Montoneros, ERP and F.A.R.) and the right-wing paramilitary group Triple A, supported by Isabel Perón, who became president of Argentina in 1974 after Juan Perón's death.