Kirby is on Farm Road 78 eight miles northeast of downtown San Antonio in eastern Bexar County. It became a station on the Galveston, Harrisburg and San Antonio Railway in 1877. In 1900 the settlement had a cotton gin, a blacksmith shop, and a population of 100. A post office operated at the site from 1907 to 1916, when service was discontinued and the mail sent to Converse. In 1930 Kirby had six businesses and twenty-five persons and in 1940 four businesses and a population of 100. The population increased to 680 by 1965, by which time the community had incorporated. Since that time the Kirby has grown rapidly, swelled by the growth of nearby San Antonio and Converse, and in 1990 the reported population was 8,326. By 2000 the population was reported as 8,673.