In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Dagenham like this:
DAGENHAM, a parish in Romford district, Essex; on an affluent of the Thames, and on the London and Southend railway, 2 miles WNW of Rainham r. station, and 3½ S by W of Romford. It includes the hamlets of Chadwell-Heath and Beacontree-Heath; and has a post office under Romford, London, E. Acres, 6, 608: of which 180 are water. Real property, £16, 607. Pop., 2, 708. Houses, 550. The property is much subdivided. The area includes 1, 359 acres of Hainault forest, and extends to the Thames. ...
An irruption of the Thames occurred here in 1703, inundating upwards of 5, 000 acres of rich land, and washing nearly 120 acres entirely away. An embankment, for preventing any similar occurrence was formed by Captain Perry, at a cost of £40, 473; and a stratum of bogwood, about 10 feet thick, with very little mixture of earth, was found, at the making of the embankment, to be about 4 feet below the surface of the soil. The living is a vicarage in the diocese of Rochester. Value, £872.* Patron, the Rev. John Farmer. The church is ancient and good. There are two Wesleyan chapels, a Free Methodist chapel, a police station, a national school, an endowed school with £270 a year, and charities £193.
A Vision of Britain through Time includes a large library of local statistics for administrative units. For the best overall sense of how the area containing Dagenham has changed, please see our redistricted information for the modern district of Barking and Dagenham. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Dagenham and units named after it.
GB Historical GIS / University of Portsmouth, History of Dagenham, in Barking and Dagenham and Essex | Map and description, A Vision of Britain through Time.
Date accessed: 27th November 2015
Click here for more detailed advice on finding places within A Vision of Britain through Time, and maybe some references to other places called "Dagenham".