Five Boroughs of the Danelaw in the context of "Derby, England"

Derby (/ˈdɑːrbi/ DAR-bee) is a cathedral city and unitary authority area on the River Derwent in Derbyshire, England. Derbyshire is named after Derby, which was its original county town. As a unitary authority, Derby is administratively independent from Derbyshire County Council. The population of Derby is 274,149 (2024).

The Romans established the town of Derventio, which was later captured by the Anglo-Saxons and then by the Vikings who made Djúra-bý one of the Five Boroughs of the Danelaw. Initially a market town, Derby grew rapidly in the industrial era and was home to Lombe's Mill, an early British factory and it contains the southern part of the Derwent Valley Mills World Heritage Site. With the arrival of the railways in the 19th century, Derby became a centre of the British rail industry. Despite having a cathedral since 1927, Derby did not gain city status until 1977.

Edmund I or Eadmund I (920/921 – 26 May 946) was King of the English from 27 October 939 until his death in 946. He was the elder son of King Edward the Elder and his third wife, Queen Eadgifu, and a grandson of King Alfred the Great. After Edward died in 924, he was succeeded by his eldest son, Edmund's half-brother Æthelstan. Edmund was crowned after Æthelstan died childless in 939. He had two sons, Eadwig and Edgar, by his first wife Ælfgifu, and none by his second wife Æthelflæd. His sons were young children when he was killed in a brawl with an outlaw at Pucklechurch in Gloucestershire, and he was succeeded by his younger brother Eadred, who died in 955 and was followed by Edmund's sons in succession.

Æthelstan had succeeded as the king of England south of the Humber and he became the first king of all England when he conquered Viking-ruled York in 927, but after his death Anlaf Guthfrithson was accepted as King of York and extended Viking rule to the Five Boroughs of north-east Mercia. Edmund was initially forced to accept the reverse, the first major setback for the West Saxon dynasty since Alfred's reign, but he was able to recover his position following Anlaf's death in 941. In 942, Edmund took back control of the Five Boroughs and in 944 he regained control over the whole of England when he expelled the Viking kings of York. Eadred had to deal with further revolts when he became king, and York was not finally conquered until 954. Æthelstan had achieved a dominant position over other British kings and Edmund maintained this, perhaps apart from Scotland. The north Welsh king Idwal Foel may have allied with the Vikings as he was killed by the English in 942. The British kingdom of Strathclyde may also have sided with the Vikings as Edmund ravaged it in 945 and then ceded it to Malcolm I of Scotland. Edmund also continued his brother's friendly relations with Continental rulers, several of whom were married to his half-sisters.

Æthelstan Ætheling (Old English: Æþelstan Æþeling; early or mid 980s – 25 June 1014) was the eldest son of King Æthelred the Unready by his first wife Ælfgifu, and was the heir apparent to the kingdom until his death. He is first mentioned as a witness to a charter of his father in 993. He probably spent part of his childhood at Æthelingadene, Dean in west Sussex, and his paternal grandmother Ælfthryth may have played an important part in his upbringing. Almost nothing is known of his life, although he seems to have formed a friendship with Sigeforth and Morcar, two of the leading thegns of the Five Boroughs of the East Midlands.

In December 1013 the Danish king Sweyn conquered England and King Æthelred was forced into exile in Normandy, but he returned following Sweyn's death in February 1014. It is not known what became of Æthelstan and his surviving full brothers, Edmund Ironside and Eadwig, during Sweyn's rule, but they probably remained somewhere in England. Æthelstan's last mention in a charter is in one dated 1013.

The North Midlands is a loosely defined area covering the northern parts of the Midlands in England. It is not an International Territorial Level region like the East Midlands or the West Midlands.

A statistical definition in 1881 included the counties of Derbyshire, Leicestershire, Lincolnshire, Nottinghamshire and Rutland, an area historically known as the Five Boroughs of the Danelaw. A Second World War civil defence region called North Midland included the five counties and Northamptonshire. It has remained in informal use for Derbyshire and Nottinghamshire, the northern parts of Lincolnshire and Staffordshire, and sometimes the far south of Northern England. A North Midlands combined authority area was proposed in 2016 for Derbyshire and Nottinghamshire, but cancelled later that year.

Olaf Guthfrithson or Anlaf Guthfrithson (Old Norse: Óláfr Guðrøðsson [ˈoːˌlɑːvz̠ ˈɡuðˌrøðsˌson]; Old English: Ánláf; Old Irish: Amlaíb mac Gofraid; died 941) was a Hiberno-Scandinavian (Irish-Viking) leader who ruled Dublin and Viking Northumbria in the 10th century. He was the son of Gofraid ua Ímair and great-grandson of Ímar, making him one of the Uí Ímair. Olaf succeeded his father as King of Dublin in 934 and succeeded in establishing dominance over the Vikings of Limerick when he captured their king, Amlaíb Cenncairech, in 937. That same year he allied with Constantine II of Scotland in an attempt to reclaim the Kingdom of Northumbria which his father had ruled briefly in 927. The forces of Olaf and Constantine were defeated by the English led by Æthelstan at the Battle of Brunanburh in 937.

Olaf returned to Ireland in 938 but after Æthelstan's death the following year Olaf left for York where he was quickly able to establish himself as king, with his brother Blácaire mac Gofraid being left to rule in Dublin. Olaf and Æthelstan's successor Edmund met in 939 at Leicester where they came to an agreement regarding the division of England between them. This agreement proved short-lived, however, and within a few years Vikings had occupied the Five Boroughs of Derby, Leicester, Lincoln, Nottingham and Stamford. Olaf died in 941 and was succeeded in Northumbria by his cousin Olaf Cuaran. At the time of his death, the Irish annals title him "king of Danes" and "king of the Fair Foreigners and the Dark Foreigners".