Portugal has been in the media quite a bit lately, as a good place to move to, but somehow the history of the country seems obscure to me. The country's archive goes back into the mid 1600's and yes, there is a digital archive porthole for your research to begin. A special note is that Portugal has a World War II Holocaust Collection. I was humored to read that the archive page mentions there are two bars nearby!
PORTAL EHRI PROJECT EU PORTUGAL
Link to the Holocaust Collection : PORTAL EHRI JEWISH HOLOCAUST COLLECTIONS