The city developed as a major port on the Kennebec River, during which time its downtown and adjacent residential area were built up.

[1] The city of Hallowell was settled in the 1760s, and its early center layout was made in 1771.

It was eventually eclipsed in importance by Augusta, just to the north, which became the state capital.

The district includes about 450 buildings, most of which were built before 1900, with fully half standing before 1865.

One of these, built in 1813, originally housed the first bookstore located east of Portland.