Typically two-and-one-half stories, with a low hipped roof and large central dormer, American Foursquares were economical to build and comfortable to live in. Their rectangular plan maximized living space without adding expense. This brick example is one of the “Three Sisters,” three very similar homes built on the 600 and 700 blocks of South Second West between 1902 and 1912. William and Nell MacGregor moved into the “completely and artistically furnished” house after their wedding in 1913. A Scottish immigrant with a background in banking, William worked as assistant treasurer for the Missoula Mercantile Company. Nell, who grew up just a few blocks away, was an accomplished pianist, who graduated from the Strassberger Conservatory in St. Louis. After her marriage, she became a program leader for the Missoula Woman’s Club music department. The home’s longest residents were Jacob and Birdie Heydorf who lived here from 1922 into the 1970s. Jacob was plant chief for Mountain States Telephone and Telegraph; during his tenure with the company he saw the number of telephones in Missoula increase from “about 500 to more than 11,000.”