The Brazilian Army (Portuguese: Exército Brasileiro; EB) is the branch of the Brazilian Armed Forces responsible, externally, for defending the country in eminently terrestrial operations and, internally, for guaranteeing law, order and the constitutional branches, subordinating itself, in the Federal Government's structure, to the Ministry of Defense, alongside the Brazilian Navy and Air Force. The Military Police (Polícias Militares; PMs) and Military Firefighters Corps (Corpos de Bombeiros Militares; CBMs) are legally designated as reserve and auxiliary forces to the army. Its operational arm is called Land Force. It is the largest army in South America and the largest branch of the Armed Forces of Brazil. Emerging from the defense forces of the Portuguese Empire in Colonial Brazil as the Imperial Brazilian Army, its two main conventional warfare experiences were the Paraguayan War and the Brazilian Expeditionary Force, and its traditional rival in planning, until the 1990s, was Argentina, but the army also has many peacekeeping operations abroad and internal operations in Brazil. The Brazilian Army was directly responsible for the Proclamation of the Republic and gradually increased its capacity for political action, culminating in the military dictatorship of 1964–1985. Throughout Brazilian history, it safeguarded central authority against separatism and regionalism, intervened where unresolved social issues became violent and filled gaps left by other State institutions. Changes in military doctrine, personnel, organization and equipment mark the history of the army, with the current phase, since 2010, known as the Army Transformation Process. Its presence strategy extends it throughout Brazil's territory, and the institution considers itself the only guarantee of Brazilianness in the most distant regions of the country. There are specialized forces for different terrains (jungle, mountain, Pantanal, Caatinga and urban) and rapid deployment forces (Army Aviation, Special Operations Command and parachute and airmobile brigades). The armored and mechanized forces, concentrated in Southern Brazil, are the most numerous on the continent, but include many vehicles nearing the end of their life cycle. The basic combined arms unit is the brigade. Conventional military organizations train reservist corporals and privates through mandatory military service. There is a broad system of instruction, education and research, with the Military Academy of Agulhas Negras (Academia Militar das Agulhas Negras; AMAN) responsible for training the institution's leading elements: officers of infantry, cavalry, engineering, artillery and communications, the Quartermaster Service and the Ordnance Board. This system and the army's own health, housing and religious assistance services, are mechanisms through which it seeks to maintain its distinction from the rest of society. Source: Wikipedia (en)