Settlement began in the Tomball area in the early 19th century, where settlers found an open, fertile land that received adequate rainfall—perfect conditions for farming and raising cattle. It was on a land granted in 1838 to William Hurd's heirs. In 1906 the area began to boom. Railroad line engineers often noticed that the Tomball area was on the boundary between the low hills of Texas and the flat coastal plains of the Gulf, making it an ideal location for a train stop. The railroad could load more cargo on each car, because the topography gently sloped toward the Galveston ports and provided an easier downhill coast. Thomas Henry Ball, an attorney for the Trinity and Brazos Valley Railroad, convinced the railroad to run the line right through downtown Tomball. Soon after, people came in droves to this new train stop. Hotels, boarding houses, saloons, and mercantile stores all began to spring up in the area. At first, people called the area Peck, after a chief civil engineer of the railroad line. However, on December 2, 1907, the town was officially named Tom Ball, later to be shortened to one word, for Mr. Ball.
While the boom of the railroad lasted less than a decade, the oil and gas industry began to leave its mark on the area. Oil probe instruments often indicated that oil was just underneath Tomball, especially after the Spindletop gusher in Beaumont. Although early exploration came up dry, the town remained a frenzy of activity for those who dreamed of oil. Undaunted by the challenges, the persevering spirit of Tomball's citizens proved rewarding when a drill hit a 100-foot (30 m) gusher of oil on May 27, 1933. Tomball, which people began to call "a floating island of oil", was immediately flooded with over two dozen oil companies, which drew thousands of workers and boosted the economy like never before. One major player, the Humble Oil Company, struck a deal with the town through which they would provide gas free of charge to the residents in exchange for rights to drill on the land. This agreement lasted until 1988, when the reservoirs began to be depleted.
Tomball incorporated in 1933. Because of the 1933 incorporation, Houston did not incorporate Tomball's territory into its city limits.
Tomball continued to grow over the years and hit its second major boom after World War II. People began to desire a more comfortable life, so the entire area saw a shift of Texans migrating from the "big city" to the countryside. In Tomball, people could escape some of the disagreeable qualities of the city, like high taxes, traffic, and crime, but still enjoy the closeness of jobs, culture, and entertainment. In the 1970s, Tomball's population again soared. The entire "Sun Belt" experienced a huge influx of residents who desired the affordable land and housing, nice weather, low taxes, and abundant job opportunities. Over the next 20 years, Tomball's population would increase from 16,000 people in the school district area to over 85,000 residents. Today, the population within the city limits is up to 10,753, according to the 2010 U.S. Census. Over 80 percent of all homes in the area were built since 1970