Atlanta is the capital and the most populous city of the U.S. state of Georgia, as well as the core city of the ninth most populous metropolitan area in the United States. It is the county seat of Fulton County, although a small portion of the city extends into DeKalb County. As of July 2006, the city of Atlanta had a population of 486,411 and a metropolitan population of 5,138,223. Residents of the city are known as Atlantans. Between 2000 and 2006, the Atlanta metropolitan area grew 20.5%, making it the fastest growing metropolitan area in the nation.

On December 21, 1836 the Georgia General Assembly voted to build the Western and Atlantic Railroad to provide a trade route to the Midwest. Following the forced removal of the Cherokee Nation between 1838 and 1839 the newly depopulated area was opened for the construction of a railroad. The area around the eastern terminus to the line began to develop first. By 1842, the settlement had six buildings and 30 residents and the town was renamed "Marthasville". After a few renames, the Chief Engineer of the Georgia Railroad, J. Edgar Thomson, suggested that the area be renamed "Atlantica-Pacifica", which was quickly shortened to "Atlanta". The residents approved, and the town was incorporated as "Atlanta" on December 29, 1847.

During the American Civil War, Atlanta served as an important railroad and military supply hub. In 1864, the city became the target of a major Union invasion. The area now covered by Atlanta was the scene of several battles, including the Battle of Peachtree Creek, the Battle of Atlanta, and the Battle of Ezra Church. On September 1, 1864, Confederate General John Bell Hood evacuated Atlanta after a four-month siege mounted by Union General William T. Sherman and ordered all public buildings and possible Confederate assets destroyed. The next day, Mayor James Calhoun surrendered the city, and on September 7 Sherman ordered the civilian population to evacuate. He then ordered Atlanta burned to the ground on November 11 in preparation for his march south, though spared the city's churches and hospitals.

The rebuilding of the city — immortalized by the phoenix and motto "Resurgens" (Latin for "rising again") on the city seal — was gradual. From 1867 until 1888, U.S. Army soldiers occupied McPherson Barracks in southwest Atlanta to ensure Reconstruction era reforms. To help the newly freed slaves, the Federal Government set up a Freedmen's Bureau, which helped establish what is now Clark Atlanta University, one of several historically black colleges in Atlanta. In the 1960s, Atlanta was a major organizing center of the US Civil Rights Movement, with Dr. Martin Luther King and students from Atlanta's historically black colleges and universities playing major roles in the movement's leadership.