Context: The Empire of Brazil was a 19th-century state that broadly comprised the territories which form modern Brazil and Uruguay. Its government was a representative parliamentary constitutional monarchy under the rule of Emperors Dom Pedro I and his son Dom Pedro II. A colony of the Kingdom of Portugal, Brazil became the seat of the Portuguese colonial Empire in 1808, when the Portuguese Prince regent, later King Dom João VI, fled from Napoleon's invasion of Portugal and established himself and his government in the Brazilian city of Rio de Janeiro. João VI later returned to Portugal, leaving his eldest son and heir, Pedro, to rule the Kingdom of Brazil as regent. On 7 September 1822, Pedro declared the independence of Brazil and, after waging a successful war against his father's kingdom, was acclaimed on 12 October as Pedro I, the first Emperor of Brazil. The new country was huge but sparsely populated and ethnically diverse., The Paraguay River (Río Paraguay in Spanish, Rio Paraguai in Portuguese, Ysyry Paraguái in Guarani) is a major river in south-central South America, running through Brazil, Bolivia, Paraguay and Argentina. It flows about from its headwaters in the Brazilian state of Mato Grosso to its confluence with the Paraná River north of Corrientes and Resistencia., Bolivia (; ), officially known as the Plurinational State of Bolivia, is a landlocked country located in western-central South America. It is bordered to the north and east by Brazil, to the southeast by Paraguay, to the south by Argentina, to the southwest by Chile, and to the northwest by Peru. One-third of the country is the Andean mountain range, with one of its largest cities and principal economic centers, El Alto, located on the Altiplano. Bolivia is one of two landlocked countries (the other is Paraguay) that lie outside Afro-Eurasia. Bolivia is the largest landlocked country in the Americas., A landlocked state or landlocked country is a sovereign state entirely enclosed by land, or whose only coastlines lie on closed seas. There are currently 48 such countries, including four partially recognised states. Only two, Bolivia and Paraguay in South America, lie outside Afro-Eurasia (the Old World)., The Americas, also collectively called America, encompass the totality of the continents of North America and South America. Together they make up most of Earth's western hemisphere and comprise the "New World". , South America is a continent located in the western hemisphere, mostly in the southern hemisphere, with a relatively small portion in the northern hemisphere. It is also considered a subcontinent of the Americas, which is the model used in nations that speak Romance languages. The reference to South America instead of other regions (like Latin America or the Southern Cone) has increased in the last decades due to changing geopolitical dynamics (in particular, the rise of Brazil)., Uruguay, officially the Oriental Republic of Uruguay, is a country in the southeastern region of South America. It borders Argentina to its west and Brazil to its north and east, with the Río de la Plata (River of Silver) to the south and with the Atlantic Ocean to the southeast. Uruguay is home to an estimated 3.42 million people, of whom 1.8 million live in the metropolitan area of its capital and largest city, Montevideo. With an area of approximately , Uruguay is geographically the second-smallest nation in South America, only larger in size than Suriname., Argentina, officially the Argentine Republic, is a federal republic in the southern half of South America. Sharing the bulk of the Southern Cone with its neighbor Chile to the west, the country is also bordered by Bolivia and Paraguay to the north, Brazil to the northeast, Uruguay and the South Atlantic Ocean to the east, and the Drake Passage to the south. With a mainland area of , Argentina is the eighth-largest country in the world, the second largest in Latin America, and the largest Spanish-speaking one. The country is subdivided into twenty-three provinces (singular "provincia") and one autonomous city ("ciudad autónoma"), Buenos Aires, which is the federal capital of the nation as decided by Congress.
The provinces and the capital have their own constitutions, but exist under a federal system., Paraguay, officially the Republic of Paraguay, is a landlocked country in central South America, bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. Paraguay lies on both banks of the Paraguay River, which runs through the center of the country from north to south. Due to its central location in South America, it is sometimes referred to as "Corazón de Sudamérica" ("Heart of South America"). Paraguay is one of the two landlocked countries (the other is Bolivia) that lie outside Afro-Eurasia. Paraguay is the smallest landlocked country in the Americas., Afro-Eurasia, Afroeurasia, or Eurafrasia, is the combination of Africa and Eurasia (Europe and Asia) which together form the largest contiguous landmass on Earth. The term is a portmanteau of the names of its constituent parts., The Paraguayan War, also known as the War of the Triple Alliance and the Great War in Paraguay, was a South American war fought from 1864 to 1870 between Paraguay and the Triple Alliance of Argentina, the Empire of Brazil, and Uruguay. With an estimated 400,000 deaths, the war was the deadliest and bloodiest in Latin America's history. It particularly devastated Paraguay, which suffered catastrophic losses in population - almost 70% of its adult male population died, according to some counts - and was forced to cede territory to Argentina and Brazil. According to some estimates, Paraguay's pre-war population of 525,000 was reduced to 221,000, of which only 28,000 were men., Mato Grosso ( lit. "Thick Bushes") is one of the states of Brazil, the third largest by area, located in the western part of the country., The Mato Grosso campaign was an early Paraguayan offensive in the Paraguayan War . Paraguay captured the Brazilian province of Mato Grosso ., Brazil, officially the Federative Republic of Brazil, is the largest country in both South America and Latin America. As the world's fifth-largest country by both area and population, it is the largest country to have Portuguese as an official language and the only one in the Americas. Bounded by the Atlantic Ocean on the east, Brazil has a coastline of . It borders all other South American countries except Ecuador and Chile and covers 47.3% of the continent's land area. Its Amazon River basin includes a vast tropical forest, home to diverse wildlife, a variety of ecological systems, and extensive natural resources spanning numerous protected habitats. This unique environmental heritage makes Brazil one of 17 megadiverse countries, and is the subject of significant global interest and debate regarding deforestation and environmental protection., Subject: mato grosso campaign, Relation: part_of, Options: (A) africa (B) center (C) city (D) country (E) dynamics (F) earth (G) empire (H) eurasia (I) forest (J) government (K) guarani (L) language (M) latin america (N) monarchy (O) north america (P) ocean (Q) october (R) part (S) population (T) rio (U) river (V) romance languages (W) silver (X) southern cone (Y) sovereign state (Z) state ([) the americas (\) the republic (]) war (^) war of the triple alliance
Output: war of the triple alliance