Today's world of e-mails, text messages, and social media posts reminds us that letter-writing is an age-old practice that has continually re-invented itself culturally and contextually, connecting individuals and creating communities that may be local or global, personal or public, purposeful or playful, actual or virtual. Yet we have barely begun to explore why letter-writing matters: how it teaches us important lessons, across historical, cultural, and geographical boundaries, about being human. Letterworlds turns to the past - to the late nineteenth century - in order to explore questions of crucial relevance to our present: questions of subjectivity, solitude, and community, physical and mental wellbeing, ethics, and the everyday. Using a fresh holistic and thematic methodology, Susan Harrow examines how such issues suffuse and animate the letter-writing of a group of writers and artists whose contributions are seminal in the development of Western aesthetic modernity: Mallarmé, Morisot, Van Gogh, Cézanne, and Zola.