RAINBOW, TEXAS. Rainbow is on Farm Road 200 four miles northeast of Glen Rose in northeast Somervell County. Among the first settlers was William Porter, who established a school in the late 1860s; for several decades the area was referred to as the Porter school district. By the 1890s a community had developed, and the residents requested a post office. When the townspeople gathered to name the community a thunderstorm broke out, followed by a rainbow. The residents, struck by the beauty of the rainbow, named their town after it. A post office was opened in Rainbow in 1899. By 1910 the community had half a dozen stores, a church, and a school. In the 1920s a newspaper, the Rainbow Reminder, served the estimated 113 residents. Throughout the twentieth century Rainbow has served as a church and school community for area farmers. After the 1920s the population decreased, reaching a low of forty in 1960. By 1981 the number of residents had increased to seventy-six. This growth may be due in part to the opening of nearby Dinosaur Valley State Park in the 1970s. Through 2000 the population was still reported as seventy-six.
W. C. Nunn, Somervell: Story of a Texas County (Fort Worth: Texas Christian University Press, 1975). Kathleen E. and Clifton R. St. Clair, eds., Little Towns of Texas (Jacksonville, Texas: Jayroe Graphic Arts, 1982).