Zone of Viking-controlled territory in northern and eastern England established after the Great Heathen Army's invasion, where Danish law and customs prevailed.
Ended as a political entity in 954 when the last Viking king Eric Bloodaxe was killed at the Battle of Stainmore, bringing all England under Anglo-Saxon rule.
Comprehensive history of the Viking Age including the Danelaw — verified via Open Library (note: Open Library returned erroneous year 1661; standard edition is 1968).
The contemporary primary source recording the Great Heathen Army's invasion and the establishment of Danish-controlled territory in England.