As a detailed study of the human animal, described by its author as the raison d'etre of nature, Book Seven of the elder Pliny's Natural History is crucial to the understanding of the work as a whole. In addition, however, it provides a valuable insight into the extraordinary complex of ideas and beliefs current in Pliny's era, many of which have resonances for other eras and cultures. The present study includes a substantial introduction examining the background to Pliny's life, thought, and writing, together with a modern English translation, and a detailed commentary which emphasizes the importance of Book Seven as possibly the most fascinating cultural record surviving from early imperial Rome.