Loa, the county seat of Wayne County, was established in 1878 by approximately forty families. The name Loa was suggested by Franklin W. Young, who had once resided in the Hawaiian Islands and had been impressed with Mauna Loa, Hawaii's second highest mountain, whose name means high, large, and powerful. The city is located in a broad valley west of the Fremont River, 205 miles south of Salt Lake City and 50 miles east of Richfield; its elevation is approximately 7,000 feet.

Until 1880 the settlers were scattered throughout the valley. Under direction of the LDS church leadership, they were encouraged to build a more organized town upon the present site. The town was marked off in six-acre blocks, sixteen rods apart, and was dedicated in 1885. It was not until 1890 that residents of Loa received government title to the land. Alvin L. Robinson, a probate judge appointed by President Grover Cleveland, secured title to the town's lands and sold individual land owners their appropriate titles. Loa was incorporated on 17 April 1919 with W.S. McClellan serving as first president of the town board of trustees. Loa's early water supply came from open ditches or from settlers hauling barrels of water long distances from Brian Springs on Spring Creek. As the human and animal populations grew, concerns over contamination increased; the result was a fresh-water pipeline from Road Creek which was completed in 1911.

The town developed quickly. The town meeting house, completed in 1880, served as a school and social hall; a separate rock schoolhouse constructed in 1902. The first telephone line was completed in 1907. The local LDS stake tabernacle was completed and dedicated on 24 October 1909, and a public library was completed in 1919. The People's Power and Light Company was formed in 1929 and brought lights and electric power to the entire county. A thriving movie theater was completed in 1938 and continued operation until a rival theater opened in Bicknell in 1947.

The Loa Co-op Store began in 1902 to serve the growing agriculturally based community. Other businesses soon followed. The State Bank of Wayne, established in 1920 and a survivor of the Great Depression, constructed its present building in 1939. In 1947 the first cold storage plant was opened. The city constructed three parks and pavilions as well as a town office, fire house, and community center, and it took over maintenance of the city cemetery from the LDS Church in 1985. Curb and gutter improvements were added to Main Street in 1987 and the streets were paved at that time. Loa's population has fluctuated between a high of 499 in 1920 and a low of 324 in 1970. The 1990 census listed 444 residents of Loa.