Direct evidence for the earlier Latin sources and transmission of early medieval medical texts in England is sorely lacking - which has led to scholarly neglect. This is a gap this book addresses, via a close examination of the Old English medical corpus, including the Lacnunga and Bald's Leechbook, to shed light on the diffusion and reception of this knowledge. It considers exactly which Latin medical texts were used in the compilation of the Old English versions, showing that they were, in many cases, translations of Greek medical texts. From this, it argues that the Old English corpus as a whole was a creative endeavor to synthesize the best medical knowledge available at the time, from the various Latin works of Soranus of Ephesus to the sixth- or seventh-century Latin traditions of Galen of Pergamum, Oribasius of Pergamum and Alexander of Tralles. Covering over eight centuries of the textual tradition of medicine, it demonstrates that the dissemination of medical knowledge in pre-Conquest England was far wider than previously believed.