The document summarizes the Anglo-Saxon Chronicle, a collection of annals in Old English chronicling Anglo-Saxon history. The original manuscript was created in the late 9th century and different versions, or manuscripts, were updated until the 12th century. The document describes the surviving manuscripts located in various libraries and monasteries across England, which differ in dates of composition, additional local information included, and relationships to other manuscripts. It emphasizes the Anglo-Saxon Chronicle as the most important source for history in Anglo-Saxon England prior to the Norman Conquest.