Political system: Brazil has been a federal republic since the overthrow of the monarchy in 1889. Until the 1980s, governments were dominated to varying degrees by the armed forces, with periods of outright dictatorship in 1937-45 (under Getúlio Vargas) and 1964-85 (under a succession of military leaders) interspersed with periods of more or less democratic civilian rule and tentative liberalisation. The degree of autonomy of the states also varied during this period.