The Brazilian Army originates from the defense forces of the Portuguese Empire in Colonial Brazil. A Brazilian national army was designated by law for the first time in the Brazilian Empire's 1824 constitution, but land forces had already been fighting under the Brazilian flag since the proclamation of Independence in 1822. Command of these forces, until then dispersed among the viceroys and captain-generals of the captaincies, was unified under the Secretariat of State for War Affairs (later the Ministry of War) in 1822. Several units, however, trace their history back to the colonial period, such as the Old Terço of Rio de Janeiro, from 1567. The highest authority in the army was the Adjutant General, whose body, the Adjutant General's Office, was created in 1857. The Adjutant General was always a military officer and served as an intermediary between the army and the Minister of War, whose position was a political one. When the office was abolished, the chiefs of the Army General Staff (Estado-Maior do Exército; EME), created in 1899, and the Ministers of War began to compete for primacy of command. The Ministry of War won the dispute. Until 1894, a period marked by the Federalist Revolution and the Navy Revolts, the new republican regime began under the tutelage of the army (the so-called Republic of the Sword). The military were not united and lost power to the 

civilian oligarchies, which were alienated from the officer class and transformed the Public Forces of the most powerful states into "small armies", a major obstacle to the expansion of the Armed Forces' power. The period was one of struggle to assert its relevance. In this context, the federal army guaranteed central power against regionalist tendencies. By the 1890s, the army's operational capacity had fallen to a level sometimes inferior to the insurgents it faced. This and foreign policy fears sparked a military reform movement. At the beginning of the First Republic, the army was a small force of less than 15,000 men, organized in small battalions or equivalent isolated forces, without larger permanent units. Mobilization was difficult. Soldiers were recruited through voluntary service or forced conscription, they had no routine military training and served long "professional" careers without being incorporated into a reserve. Officers had academic education of a civilian nature at the Military School of Praia Vermelha (EMPV), the "scientists", or little to no education, the "tarimbeiros". In the violent 1890s, the army exhibited a poor performance in campaigns such as the War of Canudos, motivating reforms implemented by successive administrations in the Ministry of War from the turn of the century. The General Staff of the Army (EME) was created in 1896 to serve as the highest body, but it was not clear whether command of the army would be exercised by the Minister of War or the head of EME. A new system of coastal fortifications was built in Guanabara Bay over several decades.