Collected after his death by his friend and literary executor Max Brod, here are more than two decades' worth of Franz Kafka's letters to the men and women with whom he maintained his closest personal relationships, from his years as a student in Prague in the early 1900s to his final months in the sanatorium near Vienna where he died in 1924.

Sometimes surprisingly humorous, sometimes wrenchingly sad, they include charming notes to school friends; fascinating accounts to Brod about his work in its various stages of publication; correspondence with his publisher, Kurt Wolff, about...