The Danelaw refers to the part of Anglo-Saxon England where Danish (Viking) law and customs were dominant.

It was established following the invasion of the 'Great Heathen Army' in 865 CE.

The Great Heathen Army conquered the Anglo-Saxon kingdoms of Northumbria, East Anglia, and Mercia.

The kingdom of Wessex, under Alfred the Great, was the only one to successfully resist the invasion.

The Treaty of Wedmore (c. 886 CE) between Alfred and the Viking leader Guthrum formally recognized the boundaries of the Danelaw.

The Danelaw covered a large territory in northern and eastern England.

It was not a single political entity but a collection of territories ruled by different Viking leaders.

The settlement of large numbers of Danes had a lasting impact on the English language, with many Old Norse words being adopted.

Place names in the region often have Scandinavian endings, such as '-by' (village) and '-thorpe' (outlying farmstead).

The Danelaw was gradually reconquered by Alfred's successors in the 10th century, leading to the creation of a unified Kingdom of England.