with him as his bride. In the midst of angry protests from Aquilante, Bardo, and the other Guelph noblemen, Lionetto's cloak falls away, revealing not only that he is armed but is also a famous condottiere of the Ghibelline forces known as "Il Fortebrando". Lionetto's men, who had also concealed their swords, come to their captain's aid. They and Lionetto make their escape from Siena taking Gloria with them. Act 2 Outside the walls of Siena, Lionetto and the Ghibelline forces continue their siege of the city. Gloria is being held in one of his chambers under the watch of a Sienese woman. The woman urges her to accept Lionetto as her husband which would bring about peace between the two factions and prevent the destruction of Siena, "Prigioniera d'amor" (Prisoner of love). Gloria is torn between her love for Lionetto and loyalty to her father and the people of Siena, "O mia cuna fiorita" (O my flowered cradle). Gloria's brother Bardo enters her chambers in disguise and berates her for betraying her people and causing the death of their father who has just been killed defending Siena. She tells Bardo that she plans to marry Lionetto as a sacrifice to end the siege, but he demands that she kill him. Terrified of blood, she refuses to take Bardo's proffered dagger but promises to poison Lionetto instead. Bardo sings of his admiration for her, "O mia dolce sorella" (O my sweet sister), and departs. Gloria sings a prayer to the Virgin Mary, "Vergine santa" (Blessed Virgin). After a musical interlude, Lionetto returns from the battle. He kneels before Gloria and tells her that out of love for her he has ended the siege, "Pur dolente son io" (Though I grieve). She attempts to drink the poison herself rather than kill him. However, he knocks the poisoned wine to floor, and she openly declares her love for him. Act 3 Gloria and Lionetto's wedding is taking place in her family's chapel with her father's tomb in the background. The bishop and choir sing a Magnificat. After the ceremony, Lionetto embraces Bardo as a sign of peace. Bardo draws a dagger from beneath his cloak and stabs Lionetto, mortally wounding him. Bardo then tries to force Gloria from the chapel, but beside herself with grief, she refuses to leave. The sounds of battle are heard, and Bardo rushes outside with his men.