Mary Shelley's Valperga

Valperga relates the adventures of the early fourteenth-century despot Castruccio Castracani, lord of Lucca and conqueror of Florence. His armies threaten the fictional fortress of Valperga, governed by Countess Euthanasia, the woman he purports to love. At the climax of the novel, he forces her to choose between her feelings for him and her continued political independence.