"Just end my suffering..."
Tiradentes was a revolucionist warrior, and one of the Brazilian Crusaders.
He is more fitting for a Saber class. However, he is not an Heroic Spirit. The best term to call him is a zombie.
This is not the exactly same Tiradentes from history—this is the Tiradentes from history, but after the events of the Brazilian Empire Lostbelt, he became a whole new entity than his version that would be usually summonable.