William Muth was born in Wheeling, West Virginia, on October 2, 1851, the son of a German pork merchant. At the age of 18 he left West Virginia and traveled to Leavenworth, Kansas, where he entered the fur business of W.C. Lobenstein. In December 1873, Muth came to Helena, Montana Territory, as Lobenstein's agent, but shortly after his arrival decided to go into business on his own. During the 1870s and early 1880s Muth was interested in several mercantile establishments in Helena, Marysville, and Belmont, including Conrad & Muth and Bach, Cory & Co. For a few years he also ran the Helena-Marysville stage line which he had purchased from Negus and Whitehead. In 1886 Muth sold his mercantile and transportation businesses and established a Helena real estate office in partnership with James P. Porter. In December 1887, William E. Cox joined the firm and, as Porter, Muth & Cox, they became one of the most prominent real estate businesses in the city. Much of the development in the fashionable west side was due to their efforts. Porter, Muth & Cox established several subsidiary enterprises, including the Helena Real Estate Co. and the Hotel Park Syndicate. In addition to his real estate interests, William Muth served as administrator of the estate of Benjamin C. Brooke; as receiver of Greenhood, Bohm & Co.; and as real estate representative of the Conrad-Stanford Co. Muth was a Democrat and served in both the territorial and state legislatures. He also was territorial bank examiner, Lewis and Clark County commissioner and under-sheriff, and Helena city councilman. William Muth died on February 19, 1925, at the age of 73.