Danelaw

The Danelaw (/ˈdeɪnˌlɔː/, Danish: Danelagen; Norwegian: Danelagen; Old English: Dena lagu) was the part of England between the late ninth century and the Norman Conquest under Anglo-Saxon rule in which Danish laws applied. The Danelaw originated in the conquest and occupation of large parts of eastern and northern England by Danish Vikings in the late ninth century. The term applies to the areas in which English kings allowed the Danes to keep their own laws following the early tenth-century Anglo-Saxon conquest of Danish ruled eastern and northern England in return for the Danish settlers' loyalty to the English crown. "Danelaw" is first recorded in the early 11th century as Dena lage.

The Danelaw originated from the invasion of the Great Heathen Army into England in 865, but the term was not used to describe a geographic area until the 11th century. With the increase in population and productivity in Scandinavia, Viking warriors, having sought treasure and glory in the nearby British Isles, "proceeded to plough and support themselves", in the words of the Anglo-Saxon Chronicle for 876.

The Danelaw can describe the set of legal terms and definitions created in the treaties between Alfred the Great, the king of Wessex, and Guthrum, the Danish warlord, written following Guthrum's defeat at the Battle of Edington in 878, starting with the Treaty of Wedmore.

Between the aftermath of the Treaty of Wedmore and Guthrum's death in 890, the Treaty of Alfred and Guthrum was formalised, defining the boundaries of their kingdoms, with provisions for peaceful relations between the Danes and the Anglo-Saxons, including allowing the self-governance of the Danes in exchange of loyalty to England. The language spoken in England was affected by this clash of cultures, with the emergence of Anglo-Norse dialects.

The Danelaw approximately covered Yorkshire, the central and eastern Midlands, and the East of England.