Andrada went to Portugal as a student and became a distinguished scholar there, earning an international reputation as a naturalist and geologist. He remained in Portugal until he was 56, serving as a professor at the University of Coimbra and as the permanent secretary of the Lisbon Academy. He was deeply influenced by the principles of the Enlightenment.

Returning to Brazil in 1819, Andrada devoted himself to politics and quickly became the leading intellectual advocate of Brazilian independence from Portugal. More importantly, he became the chief adviser to the young prince regent, Dom Pedro (later the emperor Pedro I). He headed the ministry formed in January 1822 by Dom Pedro and supported Pedro in his determination that Brazil should be independent. After Pedro proclaimed Brazil's independence from Portugal (Sept. 7, 1822), Andrada became prime minister of the new empire of Brazil.

In the constituent assembly of 1823, Andrada's liberal political principles led him to oppose Pedro's Portuguese advisers, and consequently Andrada was exiled until 1829. He was then allowed to aid Pedro I once again, and he worked for the imperial cause even after Pedro's abdication (April 7, 1831). He became tutor to the child emperor Pedro II, and the liberal education that he gave Pedro II helped the latter become an effective and enlightened monarch. After being arrested in 1833 for political intrigue, Andrada retired from public life.