The Carmen de Hastingae Proelio is one of the most discussed sources for the Norman Conquest of England. Its authorship and date cannot be established entirely beyond dispute, but the weight of scholarly opinion supports a date of composition of 1068 or earlier, by Guy, bishop of Amiens, thus making it the earliest surviving account. Whatever its date, the Carmen remains a source of intrinsic interest and importance, and one used by some of the great chroniclers of the period, such as Orderic Vitalis. It is an epic poem, concerned with some of the most momentous events of a remarkable year, in which Halley's comet was a disturbing portent of undisclosed disasters. For this second edition, Frank Barlow has written an entirely new and substantial historical introduction, incorporating the scholarly research of a generation. He has also provided a fresh translation and notes, as well as revising the Latin text of the 1972 edition by Catherine Morton and Hope Muntz.