Hi there, since I see very little people commenting on literature in portuguese, my beloved language, I just felt like writing an introduction to it and talk a little about some of its greatest authors. Enjoy.
First comes Luís de Camões, who wrote the masterpiece The Lusiads, and epic poem that influenced the entire language and literature of everyone who speaks portuguese. He's our Dante, our Homer, our Milton. His work is an ode to Portugal, there are several allegories that glorifies this great nation. It's definitely a masterpiece worth reading. There are certainly a lot of translations of his works for several languages out there.
Next comes Father Antonio Vieira, a great catholic priest who wrote several books on christianity and gave great sermons to common and literate people. His influence was huge and his works have probably some of the most beautiful proses in lusophone literature. I don't know about translations, but there must be some in french or spanish.
Done with the history part, then starts the great classics, amongst them are Machado de Assis, Fernando Pessoa, Eça de Queirós, Castelo-Branco, José Saramago, Ariano Suassuna, Fernando Sabino and Guimarães Rosa. I will comment a little about them and their works.