Lone Oak is at the intersection of U.S. Highway 69 and Farm roads 513 and 1567, ten miles southeast of Greenville in southeastern Hunt County. The first settlers arrived in the area in the late 1850s. By the eve of the Civil War a community had developed and was named for an impressive oak tree that stood alone on the grass-covered prairie.
Postal authorities established a branch at Lone Oak in 1869. Twelve years later the tracks of the Missouri, Kansas and Texas Railroad reached the community, which was incorporated in 1890. By that time Lone Oak had become a shipping point for area farmers. It had a steam gristmill, a cotton gin, 800 residents, three churches, a school, the weekly Lone Oak Call, and over forty businesses.
The population increased to 1,200 by 1914, when the number of businesses surpassed sixty and included two banks. The population remained above 1,000 until the Great Depression and World War II. In 1945 the number of residents had declined to 735 and businesses to twenty-four. The construction of Lake Tawakoni two miles southwest of the town in the early 1960s slowed the decline, and in 1988 Lone Oak had 467 residents and six businesses. In 1990 and again in 2000 the population was 521.