This series of detailed studies reconsiders the monsters of Beowulf against the background of early medieval and patristic teratology in general, and other Anglo-Saxon texts in particular, in order to demonstrate the changing range of Anglo-Saxon attitudes towards the monstrous. The immediate manuscript context of the monsters in Beowulf is analyzed, as it sheds light on the poet's treatment of the theme of the monstrous and its integration into his work, and a series of parallel discussions consider a range of medieval treatments of the same theme in a variety of analogous texts (all provided with translation), in Latin, Old English, Middle Irish, and Old Icelandic.