The Lewiston Mills and Water Power Systems Historic District reflects the significance of Lewiston as an important textile manufacturing center in Maine and Northern New England from 1850 to 1950. The district?s complexes, stores, schools, commercial, industrial and social buildings and infrastructure of the predominately cotton textile industry were the stimuli for Lewiston?s development as a city, its economic success and subsequent population increases, including the prolific immigration of French-Canadians. The district includes 165 resources in total, 131 of which contribute to the district?s significance. In addition to the six extant mill complexes and power canal system, the district counts a dedicated bleachery, machine shops, social and religious buildings as well as worker housing, including three remaining company housing blocks. These events provide local and state wide significance to the Lewiston Mills and Water Power System Historic District under Criterion A for Industry, Community Planning and Development, and Social History and Ethnic History and under Criterion C for Architecture and Engineering. The level of significance is local for Community Planning and Development, Social and Ethnic History, and Architecture but the district has statewide significance in the area of Industry and Engineering. The period of significance starts in 1850, the date of the oldest extant building and structure, and ends 100 years later as the industry contracted and facilities closed.