Salt made this place. The river's own name carries the Germanic root for it, and people have been harvesting it here since at least the Bronze Age. Four brine wells - the Gutjahrbrunnen, the Meteritzbrunnen, the Deutscher Born and the Hackeborn - clustered around what is now the Hallmarkt, and what came up was concentrated enough to boil down in Koten, crude huts of reed and clay that filled the riverbank with steam. The Halloren who worked them guarded their privileges like a guild and built a treasury of silver and gold vessels, the oldest dating to 1266, which still appears on occasion at the Technical Museum Saline, where the open-pan craft of Schausieden is demonstrated. Halle appears in the written record in AD 806 and had joined the Hanseatic League by 1281. White gold, they called it. It funded everything that followed.

Halle calls itself the Stadt der fünf Türme, and the arithmetic is simple once you look up: the four towers of the Market Church, built between 1529 and 1554, plus the freestanding Red Tower across the square. In February 1546 Martin Luther's body lay in this church overnight, part-way through the procession carrying him from Eisleben, where he died, to Wittenberg, where he was buried. A small museum in the church keeps his death mask and casts of his hands. The Marienbibliothek, founded here in 1552, is Germany's oldest surviving Protestant parish library, some 36,000 titles deep. The State Museum of Prehistory guards the city's strangest treasure: the Nebra sky disc, a Bronze Age plate inlaid with a gold sun, moon and stars, dug out of a hilltop in the Unstrut valley to the southwest.

George Frideric Handel was baptised in the Market Church on 24 February 1685 and learned his craft on the little organ above its altar, taught by the church's organist Friedrich Wilhelm Zachow. His father was a barber-surgeon who is supposed to have disapproved of music; the tale of a clavichord smuggled into the attic and played after the household slept comes from Handel's first biographer and may well be embroidery. At seventeen he took a probationary year as organist at the Domkirche. By July 1703 he was in Hamburg, and he never lived in his birth city again - which has not stopped Halle claiming him. His birth house is now the Handel House museum, the Handel Festival has run since 1922 and every June since 1952, and the monument on the market square is the only one in Germany dedicated to him. Wilhelm Friedemann Bach, Johann Sebastian's eldest son, played the same church's organ from 1746 to 1764.

In 1922 an art school moved into the lower fortress of Giebichenstein Castle, on the cliffs where the Saale narrows north of the centre, and never left. It dates itself to 1 July 1915, when the architect Paul Thiersch became director; after the Weimar Bauhaus closed in 1925, a stream of its staff came to teach at Burg Giebichenstein, among them the sculptor Gerhard Marcks, who ran the place from 1928 to 1933. The city was collecting artists in those years. Lyonel Feininger came at Halle's own invitation and worked here from 1929 to 1931, producing eleven canvases known as the Halle Cycle - including Die Türme über der Stadt, those five towers again, now hanging in Cologne. The university, founded in 1694 and now joined to Wittenberg's as the Martin Luther University, kept Georg Cantor on its staff through the years when other mathematicians insisted his infinities were nonsense. The Leopoldina, Germany's oldest scientific academy, has its seat here.

The 20th century used Halle hard. During the war, prisoners from Poland, Czechoslovakia, the Soviet Union, France and the Netherlands were held at Birkhahn, a subcamp of Buchenwald, and forced to build combat aircraft at the Siebel works. Two bombing raids in the spring of 1945 killed more than a thousand people and destroyed some 3,600 buildings, the Market Church and the old town hall among them. When American troops arrived on 16 April, artillery set the Red Tower alight - but a further bombardment was called off after the former naval officer Felix von Luckner negotiated the city's surrender. Under East Germany, Halle ran on chemistry: the vast Buna and Leuna works nearby, and Halle-Neustadt thrown up in the 1960s to house their workers. Almost all of it closed after 1990. The population peaked near 305,000 in 1991 and has fallen a long way since. On 9 October 2019, Yom Kippur, a gunman tried and failed to shoot his way through the synagogue door while fifty-one people prayed inside; unable to get in, he killed Jana Lange, forty years old, in the street, and Kevin Schwarze, twenty, in a nearby kebab shop. The door held. The city has not stopped arguing about what that means.