Farmers Branch is on Interstate Highway 35 and State Highway 77 twelve miles north of downtown Dallas in northwestern Dallas County. The Burlington Northern and Missouri, Kansas and Texas railroads serve the city. Farmers Branch was the location in 1845 of the first office of the Texan Land and Emigration Company, or the Peters colony. It was the most well-known Dallas County town during the 1840s because of its advertising throughout Europe and the United States. Thomas Keenan, Isaac B. Webb, and William Cochran all arrived in 1842 and received original land grants in the area that became the site of Farmers Branch. By 1843 settlers had established a community called Mustang Branch, named for the Mustang grapes that grew along the creek. Cochran later changed the name to Farmers Branch because of the area's rich farmland.

On May 5, 1845, Isaac Webb established the first formal church in Dallas County, called Webb or Webb's Chapel. This Methodist church originally met in a log cabin, which went through several buildings but still existed as a congregation in the 1990s. A school was started in the church in 1846. Webb became the first postmaster of Farmers Branch when the post office was established there on January 5, 1848. The post office functioned until 1866, was closed, and was reinstated in 1875. The first blacksmith shop in Dallas County was built at Farmers Branch in 1845 by William Bowles, a Baptist preacher, and his slave Jordan, who worked as the blacksmith. In the same year the first Dallas County gristmill was built there; it used rawhide belts that could be used only when the weather was dry because they stretched when wet. The first local cotton gin was built in 1849 by James A. Smith.

In 1878 the Dallas and Wichita Railway was completed from Dallas to Lewisville and passed through Farmers Branch. The road went into receivership and became part of the Missouri, Kansas and Texas in 1881. By 1890 Farmers Branch had a population of 100, a district school, three general stores, two blacksmith shops, and two physicians. By World War I the population was 300, and the area was a center for grain and cotton shipments. The community had a large number of new stores, including a millinery, a lumberyard, a grocery, and the Riddle Banking Company. Telephone connections and telegraph service were available. In 1916 the first brick school building was constructed.

The population of Farmers Branch remained stable until after World War II. In April 1946 the community was incorporated and began to implement improved city services. In the next several years a new artesian well was drilled, a water tower constructed, and new water mains were laid throughout the city. A city hall and community house were built. Three industries were located in the town—a bag factory, a tile plant, and a woodworking and planing mill. The first fire station in the community was built and manned by twenty volunteer firemen. In 1956 Farmers Branch received a home-rule charter that provides for a city council-manager form of government. At that time an estimated 80 percent of the 800 residents commuted to work in Dallas.

Proximity to Dallas contributed to rapid growth. The population of Farmers Branch reached 28,550 by the mid-1970s, when a variety of manufacturers were located there. Thirty-four firms produced many items, including steel products, tile, cement, asphalt, drugs, cosmetics, machine parts, and food products. Students in Farmers Branch attended school in either the Carrollton-Farmers Branch Independent School District or the Dallas Independent School District. Areas for recreation proliferated—fifteen parks, three golf courses, seventeen tennis courts, three youth centers, two indoor theaters, and a swimming pool. Brookhaven Medical Center was completed. The Farmers Branch Times Chronicle had been published since 1956, and the Metrocrest News had been established in 1960. In the 1990s Farmers Branch had a population of 24,250, sixty Fortune 500 companies, and fifty-two manufacturers, most recently including printing and publishing firms. Brookhaven Community College and Brookhaven Country Club were within the city limits. The Farmers Branch Historical Park comprised twenty-two acres and five historic buildings. In 2000 the city population had grown to 27,508.