Following more than three centuries under Portuguese rule, Brazil peacefully gained its independence in 1822 and adopted a constitutional monarchy as its form of government. It became a federal republic following a military takeover in 1889. A coup in 1964 put Brazil under military rule for 21 years until 1985 when the military regime peacefully ceded power to civilian rulers. With a population of around 194 million, Brazil is the largest and most populous country in South America. Endowed with rich natural resources, Brazil's economy outweighs that of all other South American countries with large and well-developed agricultural, mining, manufacturing and services sectors.