Scene 1: A council chamber in the royal palace of Damascus. King Idreno is alarmed that the crusaders have crossed the Jordan River. The heathen sorceress Armida seems to have triumphed over the crusaders, but fears that her conquest is not complete without gaining the love of the Christian knight Rinaldo. Now Rinaldo is obsessed with Armida and promises to fight against his fellow Christians, if victorious King Idreno offers him the kingdom and Armida's hand. Armida prays for Rinaldo's safety.