In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Deansgate like this:
KNOTT-MILL, a railway station, with telegraph, in Manchester; on the South Junction railway, at the forking of the lines toward Altrincham and toward Liverpool, adjacent to the Bridgewater viaduct, in the W part of the city.
The location is that of Deansgate station, previously called Knott Mill. Additional information about this locality is available for Manchester
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 Deansgate has changed, please see our redistricted information for the modern district of Manchester. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Deansgate and units named after it.
GB Historical GIS / University of Portsmouth, History of Deansgate, in Manchester and Lancashire | Map and description, A Vision of Britain through Time.
Date accessed: 29th July 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 "Deansgate".