Brazil, the largest country in South America, has a federal republic. The president is the head of state and government, and is elected by the people. There is also a bicameral National Congress, consisting of the Senate and the Chamber of Deputies.
Peru has a presidential republic, with the president as head of state and government. The president is elected by the people, and there is also a single-chamber Congress.
Bolivia has a multi-party state with a president as head of state and government. The president is elected by popular vote, and there is also a bicameral Congress.
Ecuador has a presidential republic, with the president as head of state and government. The president is elected by popular vote, and there is also a single-chamber National Assembly.
Colombia has a presidential republic, with the president as head of state and government. The president is elected by popular vote, and there is also a bicameral Congress.
Venezuela has a federal republic, with a president as head of state and government. The president is elected by popular vote, and there is also a unicameral National Assembly.
Guyana has a parliamentary republic, with the president as head of state and a prime minister as head of government. The prime minister is appointed by the president, and there is also a unicameral National Assembly.
So, while the Amazon river region is home to a variety of governments, they are all democratic in nature, with elected leaders and representative bodies.
