Telephus, son of Heracles and king of Mysia, was a key figure in the Trojan War. Both enemy and ally of the Achaeans, he fought against them, was wounded and then cured by Achilles, and led Agamemnons army to Troy. This book is the first comprehensive study on his myth. It investigates fragmentary artefacts and texts, offers new readings and interpretations, and frames the evidence in its socio-political, historical, and cultural contexts. What results is a view of an ever-changing myth embedded in diverse cultural milieux, a product and a catalyst of cross-cultural exchanges, and an instrument of soft power. After assessing the sources, this book provides a contextual history of the myth, from the seventh to the first centuries BC, paying particular attention to cultural contacts in the context of migratory movements and consequent hybridisation of different social and cultural systems; repurposing and remodelling of cultural products to follow specific agendas; cultural policy and propaganda enforced through mass media and used as soft power; and more besides. All texts are translated and thus fully accessible to readers interested in myth, migration studies, cross-cultural studies, cultural history, and literary criticism.