An epistolary novel is a distinct literary genre conveyed primarily through a series of letters exchanged between fictional characters, a style that has expanded to include diary entries, newspaper clippings, and even modern electronic communications like emails and blog posts. Derived from the Greek word "epistolē" meaning letter, this format enhances realism and allows authors to present multiple character perspectives without an omniscient narrator.

While its exact genesis is debated, early examples include the Spanish Prison of Love (c. 1485) by Diego de San Pedro and the influential Letters of a Portuguese Nun (1669). The genre significantly developed with Aphra Behn's Love-Letters Between a Nobleman and His Sister (1684-87), which innovatively explored intricate plots and shifting viewpoints. The epistolary novel reached the height of its popularity in the 18th century, particularly through Samuel Richardson's hugely successful works such as Pamela (1740) and Clarissa (1749), solidifying its important role in literary history.