Fun fact: Rio de Janeiro was the capital of Portugal from 1808 to 1821 when the royal family fled to Brazil to escape Napoleon's invasion.

After Napoleon was defeated, the royal family didn't want to return and a revolution started in Portugal. The revolutionaries demanded the immediate return of the royal court in order to "restore the metropolitan dignity".

The royal family was forced to return in 1821, restoring the Portuguese Empire's full glory. Which didn't last very long. Brazil declared its independence one year later.