In A Duel with Aunt Rebecca, we are introduced to James Shields, a young Irish immigrant who has carved out a place for himself in Illinois politics as the state auditor. In 1842, Shields faces a significant challenge when he makes a decision that renders the state bank's money worthless, drawing the ire of the Whig party. As he navigates the political landscape, he becomes the target of scathing criticism, particularly from a mysterious writer known as Aunt Rebecca, whose letters published in a rival newspaper mock his integrity and competence.