The history of Belgrade dates back to at least 5700 BC. One of the largest prehistoric cultures of Europe, the Vinča culture, evolved from the Belgrade area in the 6th millennium BC. In antiquity, Thraco-Dacians inhabited the region, and after 279 BC Celts conquered the city, naming it Singidūn. It was conquered by the Romans during the reign of Augustus, and awarded city rights in the mid 2nd century. It was settled by the Slavs in the 520s, and changed hands several times before it became the capital of King Stefan Dragutin (1282–1316). In 1521 Belgrade was conquered by the Ottoman Empire and became the seat of a sanjak. It frequently passed from Ottoman to Habsburg rule, which saw the destruction of most of the city during the Austro-Ottoman wars. Belgrade was again named the capital of Serbia in 1841. The north of Belgrade remained an Habsburg outpost until 1918, when it was merged into the capital city. As a strategic location, the city was battled over in 115 wars and razed to the ground 44 times. Belgrade was the capital of Yugoslavia (in various forms of governments) from its creation in 1918, to its final dissolution in 2006.

Etymology A theory suggests that the ancient name Singidunum (Celtic: , ) actually bears its modern meaning – "White Fort (town)".

The first mention of Belgrade, in its current form, is from a letter written on 16 April 878, by Pope John VIII to Boris I Mihail, when the city was held by the Bulgarian Kingdom.

The contemporary name of Belgrade derives from the Slavic words "bel" (i.e. "white") and "grad" (i.e. "town"-"city" or "castle"-"fort"). Historically, Slavs name a place of living "grad" or "gorod" only if it has some protective walls – "ograda" in Slavic. And Slavs don't divide between "town" and "city". So the meaning of Belgrade is White City or White Castle.

Serbs write the word Beograd without "l" exactly like they pronounce it.

White City is not so uncommon as a name between Slavic people, for example: Belgorod in Russia, Bilhorod on Dniester in Ukraine, or Biograd na Moru in Croatia.

Prehistory

Chipped stone tools found at Zemun show that the area around Belgrade was inhabited by nomadic foragers in the Palaeolithic and Mesolithic eras. Some of these tools belong to the Mousterian industry, which are associated with Neanderthals rather than modern humans. Aurignacian and Gravettian tools have also been discovered there, indicating occupation between 50,000 and 20,000 years ago.

The first farming people to settle in the region are associated with the Neolithic Starčevo culture, which flourished between 6200 and 5200 BC. There are several Starčevo sites in and around Belgrade, including the eponymous site of Starčevo. The Starčevo culture was succeeded by the Vinča culture (5500–4500 BC), a more sophisticated farming culture that grew out of the earlier Starčevo settlements which is also named for a site in the Belgrade region (Vinča-Belo Brdo). The Vinča culture is known for its very large settlements, one of the earliest settlements by continuous habitation and some of the largest in prehistoric Europe; anthropomorphic figurines such as the Lady of Vinča; the earliest known copper metallurgy in Europe; a proto-writing form developed prior to the Sumerians and Minoans, known as the Old European script, dating back to around 5300 BC.

Antiquity Pre-Roman (800 BC–75 BC) The Paleo-Balkan tribes of Thracians and Dacians were the masters of this area prior to the Roman conquest. Belgrade was inhabited by a Thraco-Dacian tribe Singi, while after the Celtic invasion in 279 BC, the Scordisci took the city, naming it "Singidūn" (dun, fortress).

Roman era (35 BC–395 AD)

The Romans reached the area of Belgrade during Octavian's Dalmatian War in 35–34 BC. It became the Romanised Singidunum in the 1st century AD, and by the mid-2nd century, the city was proclaimed a municipium by the Roman authorities, evolving into a full-fledged colonia by the end of the century.

The Romans first began to establish firm control over the lands surrounding Singidun during the late 1st century BC. Moesia was organised as a Roman province in 29 BC, and Singidun was Romanised as Singidunum. It became an important settlement of Moesia, situated between Sirmium (modern Sremska Mitrovica) and Viminacium (modern Kostolac), and just across the Sava River from Taurunum (modern Zemun) in Pannonia. Singidunum occupied a strategic position on the Danubian limes, the frontier system of roads, forts, and settlements along the river.

Singidunum reached its height after the arrival of Legio IV Flavia Felix, which was stationed there from the end of the 1st century AD. The legion built a castrum (fort) on the site of the Upper Town of today's Kalemegdan, where remains of the Roman military camp have survived. The fortress was first built with earth and timber defences and was later rebuilt in stone. The legion made Singidunum a major military centre on the frontier, while a civilian settlement developed around the camp. In time, the town took on a rectilinear construction, with its streets meeting at right angles. Traces of the Roman street plan are preserved in the orientation of parts of central Belgrade, including the area of Knez Mihailova Street, Studentski Trg, Uzun Mirkova, Dušanova, and Kralja Petra I. Studentski Trg (Students' Square) was in the area of the Roman civil settlement, where remains including thermae have been found. Other remnants of Roman material culture, such as tombs, monuments, sculptures, ceramics, and coins, have been found in Belgrade and its surroundings. Roman remains are also preserved beneath the Belgrade City Library, in the space known as the Roman Hall. Hadrian granted Singidunum the rights of municipium during the mid-2nd century, and the city later became a colonia. The Roman Emperor Jovian was born in Singidunum in 330 or 332. Singidunum and Moesia experienced a period of stability under Roman rule, but this was affected by growing turmoil both outside the Empire and within it. The Roman Empire began to decline at the end of the 3rd century. The province of Dacia, established by several successful and lengthy campaigns by Trajan, came under pressure from invading peoples during the 3rd century. By 270, Aurelian abandoned Dacia north of the Danube and reorganised the frontier south of the river. Singidunum again became a frontier stronghold on the limes, one of the major fortified settlements facing danger from groups beyond the Danube.

Middle Ages

Byzantine (395–626)

In 395, upon the death of Theodosius I, the Roman Empire was split into two, with Singidunum lying on the northwestern border of the Eastern Roman Empire (later to become the Byzantine Empire). Moesia and Illyricum suffered devastating raids by the successive invasions of the Huns, Ostrogoths, Gepids, Sarmatians, Avars, and Slavs. Singidunum fell to the Huns in 441, who razed the city and fortress, selling its Roman inhabitants into indentured servitude. Over the next two hundred years, the city passed hands several times: the Romans reclaimed the city after the fall of the Hun confederation in 454, but the Sarmatians conquered the city shortly thereafter. In 470 the Ostrogoths seized the city around, expelling the Sarmatians. The city was later invaded by Gepids (488), but the Ostrogoths recaptured it in 504. Six years later the Eastern Roman Empire reclaimed the city according to a peace treaty.

Byzantine emperor Justinian I rebuilt Singidunum in 535, restoring the fortress and city to its former military importance. The city saw a brief peaceful period of about fifty years, but was then sacked with the arrival of the Avars in 584. During Maurice's Balkan campaigns, Singidunum served as a base of operations, but it was lost again in the early half of the 7th century when the Avars sacked and burned Singidunum to the ground. Around 630, the Slavs settled in the area and in Singidunum, coordinated by a Roman fortress commander. By this time, however, the city had lost its importance as a border fortification and was largely ignored by the Slavs, who dominated the area.

Early Middle Ages In 442, the area was ravaged by Attila the Hun.The Rome that did not fall: the survival of the East in the fifth century, p.67' In 471, it was taken by Theodoric the Great, who continued into Greece.Roy E. H. Mellor, Eastern Europe: a geography of the Comecon countries, p. 43. Google Books As the Ostrogoths left for Italy, the Gepids took over the city. In 539 it was retaken by the Byzantines.Procopius, De Bello Gothico, III:34, quoted in Pohl 1997, pp. 89–90 In 577, some 100,000 Slavs poured into Thrace and Illyricum, pillaging cities and settling down. The Avars under Bayan I conquered the whole region by 582.Warriors of the Steppe: a military history of Central Asia, 500 B.C. to 1700, p. 76 According to Byzantine chronicle De Administrando Imperio, the White Serbs had stopped in Belgrade on their way back home, asking the strategos for lands; they received provinces in the west, towards the Adriatic, which they would rule as subjects to Heraclius (610–641).Bohlau, 1964, Slavistische Forschungen, Volume 6, p. 103. University of California. The first record of the name Belograd appeared on 16 April 878 in a letter"Latin Sources of the Bulgarian History, t. II, page 151" from Pope John VIII to the ruler of the Bulgarian Empire Boris I, part of which was the city. For about four centuries, the city remained a battleground between the Byzantine Empire, the Kingdom of Hungary and the Bulgarian Empire.

High Middle Ages Basil II (976–1025) installed a garrison in Belgrade.Byzantium in the year 1000,p. 121 The city hosted the armies of the First and the Second Crusade; while passing through during the Third Crusade, Frederick Barbarossa and his 190,000 crusaders saw Belgrade in ruins.

Stephen Dragutin (r. 1276–1282), received Belgrade from his father-in-law, Stephen V of Hungary in 1284; it served as the capital of the Kingdom of Syrmia, and Dragutin is regarded as the first Serbian king to rule over Belgrade.

Late Middle Ages Following the Battle of Maritsa in 1371 and the Battle of Kosovo in 1389, the Serbian Empire began to crumble as the Ottoman Empire conquered its southern territory. The north resisted through the Serbian Despotate, which had Belgrade as its capital. The city flourished under Stefan Lazarević, son of Serbian prince Lazar Hrebeljanović. Lazarević built a castle with a citadel and towers, of which only the Despot's tower and west wall remain. He also refortified the city's ancient walls, allowing the Despotate to resist the Ottomans for almost 70 years. During this time, Belgrade was a haven for many Balkan peoples fleeing Ottoman rule, and is thought to have had a population of 40,000 to 50,000 people.

In 1427, Stefan's successor Đurađ Branković had to return Belgrade to the Hungarian king, and Smederevo became the new capital. Although the Ottomans captured most of the Serbian Despotate, Nándorfehérvár – as it was known in the Kingdom of Hungary – was unsuccessfully besieged in 1440 and again in 1456. As it presented an obstacle to their advance into Hungary and further Europe, over 100,000 Ottoman soldiers launched the 1456 Siege of Nándorfehérvár, in which the Christian army under commander John Hunyadi successfully defended the city from the Ottomans, wounding Sultan Mehmed II. The noon bell ordered by Pope Callixtus III commemorates the victory throughout the Christian world to this day.

Early modern period

Ottoman conquest and Austrian invasions