Prior to the arrival of European Americans in north Georgia, Creek and Cherokee Indians inhabited the area. A Creek village located where Peachtree Creek flows into the Chattahoochee River, Standing Peachtree or Standing Pitch Tree, was the closest Indian settlement to what is now Atlanta. As part of the systematic removal of Native Americans from northern Georgia from 1802 to 1825, the Creek ceded the area that is now Metro Atlanta in 1821. White settlers arrived in 1822, and nearby Decatur was founded the following year.
In 1836, the Georgia General Assembly voted to build the Western and Atlantic Railroad in order to provide a link between the port of Savannah and the Midwest. The initial route was to run from Chattanooga to a spot called simply "Terminus," located east of the Chattahoochee River, which would eventually be linked to the Georgia Railroad from Augusta and the Macon and Western Railroad, which ran from Macon to Savannah. An engineer was chosen to recommend the location of the terminus. Once he surveyed various possible routes, he drove a stake (the “zero milepost”) into the ground in what is now Five Points. A year later, the area around the railroad terminus had developed into a settlement, first known as "Terminus" and then Thrasherville, for John Thrasher, a local merchant who built homes and a general store in the settlement. By 1842, the settlement had six buildings and 30 residents and the town was renamed "Marthasville". The Chief Engineer of the Georgia Railroad, J. Edgar Thomson, suggested renaming the area "Atlantica-Pacifica" to highlight the rail connection westwards, shortened to "Atlanta". The residents approved, and the town was incorporated as Atlanta on December 29, 1847. By 1854, another railroad connected Atlanta to LaGrange, and the town grew to 9,554 by 1860.During the Civil War, the nexus of multiple railroads in Atlanta made the city a hub for the distribution of military supplies. In 1864, following the capture of Chattanooga, the Union Army moved southward and began its invasion of north Georgia. The region now covered by Metropolitan Atlanta was the location of several major army battles, including Kennesaw Mountain, Peachtree Creek, Jonesborough (now Jonesboro), and the Battle of Atlanta. On September 1, 1864, following a four-month-long siege of the city by the Union Army under the command of General William Tecumseh Sherman, Confederate General John Bell Hood made the decision to retreat from Atlanta. General Hood ordered that all public buildings and possible assets to the Union Army be destroyed. On the next day, Mayor James Calhoun surrendered Atlanta to the Union Army, and on September 7, General Sherman ordered the city's civilian population to evacuate. On November 11, 1864, in preparation of the Union Army's march to Savannah, Sherman ordered for Atlanta to be burned to the ground, sparing only the city's churches and hospitals. After the Civil War ended in 1865, Atlanta was gradually rebuilt. From 1867 until 1888, U.S. Army soldiers occupied the McPherson Barracks in southern Atlanta to ensure that the Reconstruction era reforms were carried out.

In 1868, the Georgia State Capital was moved from Milledgeville to Atlanta due to the city's superior rail transportation network, making Atlanta the fifth location of the capital of the State of Georgia. The Confederate Soldiers' Home was built to house disabled and elderly Georgia veterans from 1901 to 1941. Henry W. Grady, the editor of the Atlanta Constitution newspaper, promoted Atlanta to potential investors as a city of the "New South", one to be built on a modern economy, less reliant on agriculture. As a focal point of this change, the Georgia Institute of Technology (its future name) was established in Atlanta in 1885 (with its first classes held in October 1888).
Increased racial tensions, the result of a media-fueled hysteria over alleged sexual assaults on white women by black men, led to the Atlanta Race Riot of 1906, which left at least 27 people dead and over 70 injured.

On May 21, 1917, the Great Atlanta Fire destroyed 1,938 buildings, mostly wooden, in what is now the Old Fourth Ward. The fire resulted in 10,000 people becoming homeless. Only one person died, a woman who died of a heart attack at seeing her home in ashes.
On December 15, 1939, Atlanta hosted the film premiere of Gone with the Wind, the epic film based on the best-selling novel by Atlanta's Margaret Mitchell. Several stars of the film, including Clark Gable, Vivien Leigh, Olivia de Havilland, and its legendary producer, David O. Selznick, attended the gala event, which was held at Loew's Grand Theatre, now demolished. The reception was held at the Georgian Terrace Hotel, which still exists.
During World War II, manufacturing industries such as the Bell Aircraft Company's large factory in the northwestern suburb of Marietta, a massive growth in railroad traffic—and the manufacture of railroad cars—for the war effort, and great growth at Fort McPherson, Fort Gillem (est. 1941), and Rickenbacker Field forced a large growth in the population and economy of Atlanta. Shortly after the war, the federal Centers for Disease Control and Prevention was founded in Atlanta.
In the 1950s, the city's newly-constructed freeway system enabled middle class Atlantans to relocate from the city to the suburbs. As a result, the city began to make up an ever smaller proportion of the metropolitan area's population, decreasing from 31% in 1960 to 9% in 2000.
During the 1960s, Atlanta was a major organizing center of the Civil Rights Movement, with Dr. Martin Luther King, Jr., Ralph David Abernathy, and students from Atlanta's historically Black colleges and universities playing major roles in the movement's leadership. In 1961, Atlanta Mayor Ivan Allen Jr. became one of the few Southern white mayors to support desegregation of his city's public schools. While minimal compared to other cities, Atlanta was not completely free of racial strife. After forced-housing patterns were outlawed, violence, intimidation and organized political pressure was used in some white neighborhoods to discourage blacks from buying homes there. However, such efforts proved futile as real estate agents began engaging in blockbusting, encouraging white homeowners to sell at rock-bottom prices so that the agents could re-sell the homes to blacks at a large profit. The resulting white flight mostly affected Atlanta's western and southern neighborhoods, many of them transitioning to majority black by the 1970s. In 1961, the city attempted to thwart blockbusting by erecting road barriers in Cascade Heights, countering the efforts of civic and business leaders to foster Atlanta as the "city too busy to hate."

African Americans became a majority in the city by 1970, and exercised new-found political influence by electing Atlanta's first black mayor, Maynard Jackson, in 1973. However, suburbanization, rising prices, a booming economy, and new migrants have decreased the black percentage of the city from a high of 69% in 1980 to 54% in 2010. From 2000 to 2010, Atlanta gained 22,763 white residents, while it lost 28,795 black residents.In 1990, Atlanta was selected as the site for the 1996 Summer Olympic Games. Following the announcement, Atlanta undertook several major construction projects to improve the city's parks, sports facilities, and transportation. Atlanta became the third American city to host the Summer Olympics. The games themselves were marred by numerous organizational inefficiencies, as well as the Centennial Olympic Park bombing.
During the 2000s, Atlanta completed its transformation into a cosmopolitan city, becoming well known for its robust cultural offerings. Much of the city's change in the last decade was been driven by young, college-educated professionals who have moved into Atlanta by the thousands, seeking a lifestyle rich in cultural variety, diversity, and excitement. From 2000 to 2009, the tree-mile radius surrounding Downtown Atlanta gained 9,722 residents aged 25 to 34 holding at least a four-year degree, an increase of 61% and the sixth-largest such increase in the nation. In fact, Atlanta is on the leading edge of a national trend: while the same growth has occurred in dozens of other American cities, the change was twice as strong in Atlanta as it was nationwide. As the city's new residents transformed communities long in decline into neighborhoods of choice, Atlanta's cultural offerings expanded to meet their increased demand. A total of 45 restaurants have opened Downtown since 2008. The High Museum of Art doubled in size and launched partnerships with major institutions such as the Louvre and New York's Museum of Modern Art. In 2007, the Alliance Theatre won a Tony Award, placing it among the nation's leading performing arts venues. The once-industrial Westside is now home to warehouse lofts, start-up companies, and buzzed-about restaurants.