It encompasses an area just west of downtown Nashua, roughly located along the southern bank of the Nashua River, bordered on the west side by Mine Falls Park, on the south side by the Nashua River canal, up to Ledge Street, and from the east side by Factory, Pine and Water streets, up to the Main Street bridge.

The district takes its name from the time when this complex of buildings belonged to the Nashua Manufacturing Company, and though surrounding buildings also served the company in some way or another, they are not included in the district.

The Nashua Manufacturing Company was originally built as a cotton mill and was incorporated in 1823.

The creation of a new railroad line to Nashua from Lowell, Massachusetts, in 1838 gave the local economy a further boost, and the Nashua Iron Company opened, specializing in locomotive parts for this growing new industry.

The Nashua Manufacturing Company built 48 houses or tenements and two churches to be able to hire enough workers to man the machinery in its complex.