Bologna (Bolognese: Bulåggna) is the capital and largest city of the Emilia-Romagna region in northern Italy. It is the seventh most populous city in Italy, with 391,473 inhabitants from 150 different nationalities. Its metropolitan province is home to more than 1 million people as of 2026. Bologna is most famous for being the home to the oldest university in continuous operation, the University of Bologna, established in AD 1088.
The city has been an important urban center for centuries, first under the Etruscans (who called it Felsina), then under the Celts as Bona, later under the Romans (Bonōnia), then again in the Middle Ages, as a free municipality and later signoria, when it was among the largest European cities by population. Famous for its towers, churches and lengthy porticoes, Bologna has a well-preserved historical centre, thanks to a careful restoration and conservation policy which began at the end of the 1970s. In 2000, it was declared European capital of culture and in 2006, a UNESCO "City of Music" and part of the Creative Cities Network. In 2021, UNESCO recognized the lengthy porticoes of the city as a World Heritage Site.
Bologna is an important agricultural, industrial, financial and transport hub, where many large mechanical, electronic and food companies have their headquarters, and is also home to one of the largest permanent trade fairs in Europe. In 2022, Il Sole 24 Ore named Bologna the best city in Italy for overall quality of life, although it dropped to 4th place in 2025. Bologna intends to become carbon neutral by 2040 and raise female employment rates, focusing on sustainable and equitable urban development. The city is also increasing its investment in sustainability as part of a 2022–2024 program that integrates gender perspectives into urban planning, with an emphasis on sustainable mobility, public infrastructure, and green spaces.
Traces of human habitation in the area of Bologna go back to the 3rd millennium BCE, with significant settlements from about the 9th century BCE (Villanovan culture). The influence of Etruscan civilization reached the area in the 7th to 6th centuries, and the Etruscan city of Felsina was established at the site of Bologna by the end of the 6th century. By the 4th century BCE, the site was occupied by the Gaulish Boii, and it became a Roman colony and municipium with the name of Bonōnia in 196 BCE. During the waning years of the Western Roman Empire Bologna was repeatedly sacked by the Goths. It is in this period that legendary Bishop Petronius, according to ancient chronicles, rebuilt the ruined town and founded the basilica of Saint Stephen. Petronius is still revered as the patron saint of Bologna.
In 727–728, the city was sacked and captured by the Lombards under King Liutprand, becoming part of that kingdom. These Germanic conquerors built an important new quarter, called addizione longobarda (Italian meaning 'Longobard addition') near the complex of St. Stephen. In the last quarter of the 8th century, Charlemagne, at the request of Pope Adrian I, invaded the Lombard Kingdom, causing its eventual demise. Occupied by Frankish troops in 774 on behalf of the papacy, Bologna remained under imperial authority and prospered as a frontier mark of the Carolingian Empire.
Bologna was the center of a revived study of law, including the scholar Irnerius (c. 1050 – after 1125) and his famous students, the Four Doctors of Bologna. Bologna boasts of having one of the oldest universities in the western world (University of Bologna), with a continuous operation since 1088, and the first university in the sense of a higher-learning and degree-awarding institute. The university originated as a centre for the study of medieval Roman law under major glossators, including Irnerius. It numbered Dante, Boccaccio and Petrarch among its students. The medical school was especially renowned. By 1200, Bologna was a thriving commercial and artisanal centre of about 10,000 people.
After the death of Matilda of Tuscany in 1115, Bologna obtained substantial concessions from Emperor Henry V. However, when Frederick Barbarossa subsequently attempted to strike down the deal, Bologna joined the Lombard League, which then defeated the imperial armies at the Battle of Legnano and established an effective autonomy at the Peace of Constance in 1183. Subsequently, the town began to expand rapidly and became one of the main commercial trade centres of northern Italy thanks to a system of canals that allowed barges and ships to come and go.
During a campaign to support the imperial cities of Modena and Cremona against Bologna, Frederick II's son, King Enzo of Sardinia, was defeated and captured on 26 May 1249 at the Battle of Fossalta. Although the emperor demanded his release, Enzo was thenceforth kept a knightly prisoner in Bologna, in a palace that came to be named Palazzo Re Enzo after him. Every attempt to escape or to rescue him failed, and he died after more than 22 years in captivity. After the death of his half-brothers Conrad IV in 1254, Frederick of Antioch in 1256 and Manfred in 1266, as well as the execution of his nephew Conradin in 1268, he was the last of the Hohenstaufen heirs.
During the late 13th-century, Bologna was affected by political instability when the most prominent families incessantly fought for the control of the town. The free commune was severely weakened by decades of infighting, allowing the pope to impose the rule of his envoy Cardinal Bertrand du Pouget in 1327. Du Pouget was eventually ousted by a popular rebellion and Bologna became a signoria under Taddeo Pepoli in 1334. By the arrival of the Black Death in 1348, Bologna had 40,000 to 50,000 inhabitants, reduced to just 20,000 to 25,000 after the plague.
In 1350, Bologna was conquered by archbishop Giovanni Visconti, the new lord of Milan. But following a rebellion by the town's governor, a renegade member of the Visconti family, Bologna was recovered by the papacy in 1363 by Cardinal Gil Álvarez Carrillo de Albornoz after a long negotiation involving a huge indemnity paid to Bernabò Visconti, Giovanni's heir, who died in 1354. In 1376, Bologna again revolted against Papal rule and joined Florence in the unsuccessful War of the Eight Saints. However, extreme infighting inside the Holy See after the Western Schism prevented the papacy from restoring its domination over Bologna, so it remained relatively independent for some decades as an oligarchic republic. In 1401, Giovanni I Bentivoglio took power in a coup with the support of Milan, but, having turned his back on them and allied with Florence, the Milanese marched on Bologna and had Giovanni killed the following year. In 1442, Hannibal I Bentivoglio, Giovanni's nephew, recovered Bologna from the Milanese, only to be assassinated in a conspiracy plotted by Pope Eugene IV three years later. But the signoria of the Bentivoglio family was then firmly established, and the power passed to his cousin Sante Bentivoglio, who ruled until 1462, followed by Giovanni II. Giovanni II managed to resist the expansionist designs of Cesare Borgia for some time, but on 7 October 1506, Pope Julius II issued a bull deposing and excommunicating Bentivoglio and placing the city under interdict. When the papal troops, along with a contingent sent by Louis XII of France, marched against Bologna, Bentivoglio and his family fled. Julius II entered the city triumphantly on 10 November.
The period of papal rule over Bologna (1506–1796) has been generally evaluated by historians as one of severe decline. However, this was not evident in the 1500s, which were marked by some major developments in Bologna. In 1530, Emperor Charles V was crowned in Bologna, the last to be crowned by the pope. In 1564, the Piazza del Nettuno and the Palazzo dei Banchi were built, along with the Archiginnasio, the main building of the university. The period of Papal rule saw also the construction of many churches and other religious establishments, and the restoration of older ones. At this time, Bologna had ninety-six convents, more than any other Italian city. Painters working in Bologna during this period established the Bolognese School which includes Annibale Carracci, Domenichino, Guercino, and others of European fame.