Until the 19th century, there was very little population in the area compared to the present day borough: only a few present settlements appear in the Domesday Book, although Bexley's charter dates back to 814 AD. Until the late 19th century, Erith was a port on the Thames; the opening of Crossness's sewage works in the late 19th century transformed it into an industrial centre.
Until the 19th century, it was an area with few isolated buildings, including the Georgian Danson House. The settlement pattern of today is a result of the gradual extension of London influence. Although the area has still been a mix of many disconnected settlements interspersed with open ground and parks, construction began apace with the arrival of the railways.
The London Borough of Bexley was created in 1965, under the London Government Act 1963, from the Municipal Boroughs of Bexley and Erith, the Crayford Urban District, and part of Chislehurst and Sidcup. Before it established new Civic Offices at the former Woolwich headquarters in 2014, meetings were held at Erith Town Hall. In 1980, the council constructed the new Civic Offices on the south side of the Broadway in Bexleyheath.
According to its formal name, the council is now known as "London Borough of Bexley", but it was previously known as "Bexley London Borough" until 1999 (possibly to retain a link with its predecessor, Bexley Municipal Borough), and as "Bexley Council" until October 2007, when it reverted to its full name as part of the adoption of the new Council logo bearing its name together with the 1965 Coats of Arms.
Located on the outer edge of London, Bexley has a lot of open space. From its highest point at Shooters Hill, on the boundary with the Royal Borough of Greenwich, to its end at Belvedere, where the land drops down to the old port of Erith, South London is covered by the ridge of higher ground.
Its geology is characterised by sand and pebbles from the Blackheath beds, which produces heathland, which served as a natural course for the Roman road between Crayford and Welling, Watling Street. At Crossness, the River Thames loops to the north of the high ground as the land falls away to the north of the high ground.
In the west, there is another ridge terminating at Sidcup with less higher ground. Besides the Thames, the other rivers in the Borough include the River Darent, along with its tributaries the River Cray and the smaller Stanham River, which all form its north-eastern boundary; and the River Shuttle, which is a tributary of the Cray.
It is possible to divide settlements into two parts: the older, former villages and the suburban infill areas. Among the former are Erith, in the Arab district.ed Urban District Councils (UDC), as was Foots Cray (an ancient village site). Thamesmead, the "new town" built on what was the Erith Marshes, extends into the Borough: both Thamesmead North and South are located here. Crayford was mentioned in the Domesday Book, and its parish later included the hamlets of North End and Slade Green.
There are also several settlements in Bexley UDC, including Welling, which has a higher population than Bexleyheath, and a staging post on the Dover Road which was once of lesser importance than nearby East Wickham (also an ancient village). In the Cray Valley, Barnes Cray and North Cray were two hamlets; Belvedere was the site of a medieval monastery.
Bexley shares boundaries with the south London Borough of Bromley as well as the Royal Borough of Greenwich to the west. It borders the London Boroughs of Havering and Barking and Dagenham on the north side of the River Thames; on the northeast, it borders Thurrock in Essex. To the east it shares a boundary with Dartford and to the south east it shares a boundary with the Sevenoaks district.