Great Britain Historical GIS

The Great Britain Historical GIS (or GBHGIS), is a spatially enabled database that documents and visualises the changing human geography of the British Isles, although is primarily focussed on the subdivisions of the United Kingdom mainly over the 200 years since the first census in 1801. The project is currently based at the University of Portsmouth, and is the provider of the website A Vision of Britain through Time.

NB: A "GIS" is a Geographic Information System, which combines map information with statistical data to produce a visual picture of the iterations or popularity of a particular set of statistics, overlaid on a map of the geographic area of interest.

The first version of the GB Historical GIS was developed at Queen Mary, University of London between 1994 and 1999, although it was originally conceived simply as a mapping extension to the existing Labour Markets Database (LMDB). The system included digital boundaries for Registration Districts and Poor Law Unions (c.1840 to 1911), Local Government Districts (1911 to 1974), and Parishes (1870s to 1974). These boundaries were held not as polygons but as line segments (arcs), using ArcGIS software. Dates of creation and abolition were held for each line segment (or "arc") and custom software was developed to assemble line segments into polygons, creating conventional boundary maps for particular dates. Meanwhile, the Labour Markets Database evolved into the Great Britain Historical Database (GBHDB), which stored a large collection of historical statistics from the census, vital registration and records of poverty and economic distress. These were held in thousands of columns within hundreds of separate tables, within an Oracle database. This system is described in detail in Gregory and Southall (1998), and in Gregory and Southall (2002).

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