On July 14, 1864 four miners, dubbed the "Four Georgians" (though only one was from Georgia), discovered gold in a creekbed along what today is Helena's downtown main street, Last Chance Gulch.

The city grew from south to north along Last Chance Gulch, its main street, and hence the evolution of architectural styles can be traced.

[3] Few major downtown buildings were built in the years immediately after the Panic of 1893, which among other problems, caused the closing of the local silver mines.

[3] A major fire in 1928 affected the area, destroying many original buildings, including the Granite, Bailey, Gold, and New York Store blocks.

[3] Helena's early commercial district was located along State, Edwards, and Broadway Streets, but fires destroyed much of this area in 1869, 1872, and 1874.

[7] Urban renewal was viewed by many locals as a "disaster" equal to the 1935 earthquake, as many "insipid" new buildings were put on in the place of demolished historic structures.

Mansions in this section include those once owned by United States Senator Thomas C. Power, B. H. Tatum, D. A. G. Floweree, and S. T. Hauser.

[16] Approximately three blocks of mixed commercial and residential buildings centered on North Rodney Street, east of the earlier downtown section, were added to the district in 1993.

Many of these structures were built in the late 1800s in an effort to move to an area considered safer than those ravaged by the earlier Helena fires.