The Franks Casket (or the Auzon Casket) is a small Anglo-Saxon whale's bone (not "whalebone" in the sense of baleen) chest from the early 8th century, now in the British Museum. The casket is densely decorated with knife-cut narrative scenes in flat two-dimensional low-relief and with inscriptions mostly in Anglo-Saxon runes. Generally thought to be of Northumbrian origin, it is of unique importance for the insight it gives into early Anglo-Saxon art and culture. Both identifying the images and interpreting the runic inscriptions has generated a considerable amount of scholarship.

The imagery is very diverse in its subject matter and derivations, and includes a single Christian image, the Adoration of the Magi, along with images derived from Roman history (Emperor Titus) and Roman mythology (Romulus and Remus), as well as a depiction of at least one legend indigenous to the Germanic peoples: that of Weyland the Smith. It has also been suggested that there may be an episode from the Sigurd legend, an otherwise lost episode from the life of Weyland's brother Egil, a Homeric legend involving Achilles, and perhaps even an allusion to the legendary founding of England by Hengist and Horsa.

The inscriptions "display a deliberate linguistic and alphabetic virtuosity; though they are mostly written in Old English and in runes, they shift into Latin and the Roman alphabet; then back into runes while still writing Latin". Some are written upside down or back to front. It is named after a former owner, Sir Augustus Wollaston Franks, who gave it to the British Museum.