Kountze is at the junction of Farm roads 418 and 1293, State Highway 326, and U.S. Highway 69/287, twenty-seven miles northwest of Beaumont in central Hardin County. It was named for Herman and Augustus Kountze, financial backers of the Sabine and East Texas Railroad, and became a station on the line. Retail businesses and lumbermen accompanied the railroad; sawmills were established at Plank, Nona, and Olive, all within three miles of Kountze. A post office was opened there in 1882. An attempt in 1884 to make Kountze the county seat failed by eleven votes. However, after a courthouse fire in 1886, voters reversed their earlier decision and overwhelmingly made Kountze the Hardin county seat the following year.
The arrival of the Gulf, Colorado and Santa Fe Railway in 1902 gave Kountze an east-west route to join the older north-south line. Kountze voters agreed to incorporate their thriving lumber and retail community in 1902. By 1910 the population, which had been 295 in 1890, was estimated to be 1,000. Kountze was one of the first towns in Hardin County with electricity. The decline of the area's lumber industries, however, along with a fire in 1916, slowed development, as did the growth of nearby Silsbee. By the mid-1940s the population of Kountze had fallen to 800.
Nearby oil discoveries during the early 1950s once again sparked the town's growth and allowed renovation of many of the city's aging utilities and roads. Under the guidance of Archer Fullingim, the Kountze News became known for its advocacy of the Big Thicket preserve and for its liberal politics during the 1960s. The population, bolstered by the presence of the county government and the migration of numerous former residents of Jefferson County into Hardin County during the 1970s, had increased to 2,716 by 1980. In 1990 it was 2,056. The population was 2,115 in 2000.