After Parliament passes measures granting rights to Britain’s Catholics in June 1780, violent anti-Catholic riots break out in London. Several places in the city go up in flames. The king is forced to issue a proclamation enforcing peace. Boswell and Johnson are both disgusted by the riots and the “dark and malignant spirit of persecution” (1053) that they show—“the most horrid series of outrage that ever disgraced a civilized country” (1053). This reaction shows that Johnson and Boswell esteem liberty as a core value of British society. Boswell describes the events despite not having witnessed them personally (he was not in London at this time) and conveys the details in part through Johnson’s letters to Mrs. Thrale. Boswell’s later dismissal of Mrs. Thrale as Johnson’s biographer may owe something to the fact that he must rely on her accounts for his narrative—rather than invoking a spirit of collaboration, he insists on distancing himself from a would-be competitor that he depends on.

In 1781, Johnson completes The Lives of the Poets, his last major work, consisting of biographies of the major English poets over several centuries. The project had started out modestly as a series of biographical prefaces to an edition of poetry; as Johnson worked, the book expanded greatly in scope and is considered today one of his major works of criticism and biography.