Gainsborough is a town 15 miles north-west of Lincoln

Lincoln, Lincolnshire

Lincoln is a cathedral city and county town of Lincolnshire, England.The non-metropolitan district of Lincoln has a population of 85,595; the 2001 census gave the entire area of Lincoln a population of 120,779....

 on the River Trent

River Trent

The River Trent is one of the major rivers of England. Its source is in Staffordshire on the southern edge of Biddulph Moor. It flows through the Midlands until it joins the River Ouse at Trent Falls to form the Humber Estuary, which empties into the North Sea below Hull and Immingham.The Trent...

 within the West Lindsey

West Lindsey

West Lindsey is a local government district in Lincolnshire, England.-History:The district was formed on 1 April 1974, from the urban districts of Gainsborough, Market Rasen, along with Caistor Rural District, Gainsborough Rural District and Welton Rural District...

 district of Lincolnshire

Lincolnshire

Lincolnshire is a county in the east of England. It borders Norfolk to the south east, Cambridgeshire to the south, Rutland to the south west, Leicestershire and Nottinghamshire to the west, South Yorkshire to the north west, and the East Riding of Yorkshire to the north. It also borders...

, England. At one time it served as an important port with trade downstream to Hull

Kingston upon Hull

Kingston upon Hull , usually referred to as Hull, is a city and unitary authority area in the ceremonial county of the East Riding of Yorkshire, England. It stands on the River Hull at its junction with the Humber estuary, 25 miles inland from the North Sea. Hull has a resident population of...

, and was the most inland in England, being more than 55 miles from the North Sea

North Sea

In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...

.

Gainsborough was one of the capital cities of Mercia

Mercia

Mercia was one of the kingdoms of the Anglo-Saxon Heptarchy. It was centred on the valley of the River Trent and its tributaries in the region now known as the English Midlands...

 during the Anglo-Saxon

Anglo-Saxon

Anglo-Saxon may refer to:* Anglo-Saxons, a group that invaded Britain** Old English, their language** Anglo-Saxon England, their history, one of various ships* White Anglo-Saxon Protestant, an ethnicity* Anglo-Saxon economy, modern macroeconomic term...

 period, which had preceded Danish

Denmark

Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...

 rule. It is understandable that the Viking

Viking

The term Viking is customarily used to refer to the Norse explorers, warriors, merchants, and pirates who raided, traded, explored and settled in wide areas of Europe, Asia and the North Atlantic islands from the late 8th to the mid-11th century.These Norsemen used their famed longships to...

 kings would have been drawn to it as an administrative centre, being close to the Danish stronghold at Torksey.

In 868 King Alfred married Ealswitha

Ealhswith

Ealhswith or Ealswitha was the daughter of a Mercian nobleman, Æthelred Mucil, Ealdorman of the Gaini. She was married in 868 to Alfred the Great, before he became king of Wessex. In accordance with ninth century West Saxon custom, she was not given the title of queen. -Life:Ealswith was the...

, daughter of Aethelred Mucill, chief of the Gaini

Gaini

The Gaini were an early Anglo-Saxon tribe. Their location cannot now be identified, but they are thought to have been one of the tribes which made up the kingdom of Mercia....

, whence the town gets its name.

Historically, Gainsborough is the "capital that never was".