Cologne through the ages

In 39 BC the Germanic Ubii came to terms with the forces of Marcus Vipsanius Agrippa and settled on the left bank of the Rhine, their centre at Oppidum Ubiorum doubling as a Roman military base. In AD 50 Agrippina the Younger, born there and married to the emperor Claudius, had her home raised to the rank of colonia, a city under Roman law, as Colonia Claudia Ara Agrippinensium. Five Roman trunk roads met the Rhine at this point, and the river itself served as a transport route. It became capital of the province of Germania Inferior and held some 45,000 people, and from 260 to 271 was capital of the breakaway Gallic Empire under Postumus, Marius and Victorinus.

Constantine I bridged the Rhine here in 310, guarded by the fort of Divitia, which later became the Cologne district of Deutz. A Jewish presence is documented in 321, when an edict of Constantine allowed Jews to be elected to the city council; that edict is the oldest documented evidence of Jews in Germany. Franks pillaged the city repeatedly in the fourth century and it fell to the Ripuarian Franks in 462. Where most Roman towns in the Rhineland were abandoned when Roman power broke, Cologne stayed inhabited, with about 3,000 people in the year 700 against perhaps 20,000 in late antiquity.

Charlemagne's chaplain Hildebold was raised to the new archbishopric in 795. Vikings burned the city in the winter of 881 to 882, and Henry the Fowler's reconquest early in the tenth century settled its future as a city of the Holy Roman Empire rather than of France. In 953 Otto I made his younger brother, Archbishop Bruno I, a duke, endowing him and his successors with the prerogatives of secular princes. That created the Electorate of Cologne, and by the end of the twelfth century the archbishop was one of the seven electors of the emperor.

Merchant traffic on the Rhine drove the growth: about 10,000 people in the year 1000, quadrupled to 40,000 by 1200. In 1164 Archbishop Rainald of Dassel brought the relics of the Three Kings from Milan to the cathedral, which made the city a destination for pilgrims; before the century was out Archbishop Philip von Heinsberg had walled the whole of it. The commune was formed in 1074. After the Battle of Worringen in 1288 the forces of Brabant and the citizenry captured Archbishop Siegfried of Westerburg, who bought his liberty by recognising the city's political independence, keeping only the administration of justice. The archbishops moved to Bonn and later Brühl and did not return until 1821. Building of the Gothic cathedral began in 1248 under Konrad von Hochstaden.

Cologne was a Hanseatic city from 1367 to 1669 and a leading member of the League, above all for its English trade. Its stronghold there was the Steelyard in London, a trading post with privileges the city guarded jealously: it stayed neutral in the Anglo-Hanseatic War of 1469 and accepted exclusion from the League in 1471, being taken back in 1476 once the Steelyard had been restored. Its merchants largely monopolised English tin, dominated the English trade in swords, armour and spears, and sold their wine into the same market.

Around 1500 silk cloth was probably the city's most successful export. Production was controlled by the Seidenamt, a guild in which women predominated, a practice kept up nowhere else but Paris, and a number of female guild masters grew wealthy on it; the best known, Fygen Lutzenkirchen, was among the richest citizens of Cologne around 1498. Twenty printing houses were at work by 1500, more than 1,200 editions having come off them since Ulrich Zell printed the city's first book in 1464.

Formal freedom was won at ruinous cost: when a quarrel between Archbishop Ruprecht of the Palatinate and the cathedral chapter became war in 1474, Ruprecht called in Charles the Bold of Burgundy, who besieged Neuss and threatened Cologne; the burghers armed the city and got Emperor Frederick III to intervene, and the emperor then elevated Cologne to free imperial city, a status it held until the French annexation. The war costs wrecked the city's finances for decades. A small circle of families ran the 49-member council, and the corruption became proverbial as Kölscher Klüngel; in January 1513 the burghers organised in the Gaffeln seized power, ten former councilmen were executed for misconduct, and new rules extending burghers' rights were codified that December in the Transfixbrief.

The first pogrom against the Jews of Cologne came in 1349, when they were used as scapegoats for the Black Death; in 1424 they were evicted from the city, and were not allowed back until 1798. A pamphlet war launched from Cologne early in the sixteenth century pressed for Jewish books, and the Talmud in particular, to be confiscated and burnt in order to stifle the Jewish faith. It was driven by Johannes Pfefferkorn, a Jewish convert to Catholicism, and by the Dominican inquisitor Jacob van Hoogstraaten; its target was the humanist and Hebraist Johannes Reuchlin, and it exposed the Cologne theologians to the ridicule of the Letters of Obscure Men.

Luther's writings were burned in the cathedral courtyard at the coronation of Charles V in 1520, the council resolved in 1527 to banish all Lutherans, and the preachers Adolf Clarenbach and Peter Fliesteden were handed to the archbishop and sentenced to death at the stake. Cologne remained the only one of the major imperial cities to stay Catholic. Work on the cathedral stalled after 1525 as the indulgence trade that financed it dried up, was suspended by 1560 and was not resumed until 1823. Thirty-seven people were executed for witchcraft in the city between 1435 and 1655, most under Archbishop Ferdinand of Bavaria between 1626 and 1631; one was Katharina Henot, the first known female postmaster in Germany. When Archbishop Gebhard Truchsess von Waldburg converted to the Reformed faith in 1582 the Wittelsbachs opposed him by force in the Cologne War, and the city was spared the worst of the devastation suffered by the country around it.

From the middle of the sixteenth century long-distance trade shifted away from the Rhine to the sea routes. Antwerp passed 50,000 inhabitants by 1526 and doubled again by 1560, the Hanseatic League moved its Flanders Kontor there in 1545, and Cologne merchants found it harder to compete. The League's syndic from 1556, Heinrich Sudermann of Cologne, could not persuade Elizabeth I to renew the Steelyard's privileges, and it dwindled. Portuguese, Italian and Flemish merchants avoiding the unrest in the Spanish Netherlands after 1566 settled in Cologne, and at times such outsiders handled a third of the city's long-distance trade; refugees from Antwerp settled there too, among them Jan Rubens and Anna of Saxony, wife of William of Orange.

Emperor Rudolf II convened a peace conference in the Gürzenich in 1579 that ended without agreement. The unrest cut the trade routes to Flanders, and Dutch control of the sea approaches brought the English trade almost to a halt. The city held near 40,000 people into the eighteenth century and was thought impregnable during the Thirty Years' War, profiting from the arms trade, but it had little share in the Atlantic trade and by 1700 had dropped out of western Europe's thirty largest cities. French revolutionary armies occupied Cologne and the Rhineland in 1794; the university was closed in 1798, the city became an arrondissement of the Département de la Roer, and in 1801 its citizens were granted French citizenship. The occupation ended in 1814, and the Congress of Vienna allocated Cologne to Prussia in 1815.

Prussian rule set a Catholic Rhineland against an overwhelmingly Protestant state. In 1837 Archbishop Clemens August von Droste-Vischering was imprisoned for two years over the legal status of marriages between Catholics and Protestants, and in 1874, during the Kulturkampf, Archbishop Paul Melchers was imprisoned before taking asylum in the Netherlands. Industrialisation doubled the population from 45,000 in 1810 to 90,000 in 1846, and the railway that crossed the Rhine in the heart of the city carried it to 650,000 by the First World War, partly by absorbing surrounding towns. Cologne was also made a fortress of the German Confederation, ringed by two fortified belts that blocked expansion and forced dense building within. The cathedral, begun in 1248 and abandoned around 1560, was completed in 1880, not only as a church but as a national monument to the new German empire.

After the First World War the city was occupied by the British Army of the Rhine until 1926; Konrad Adenauer, mayor from 1917 to 1933, credited the comparatively lenient British approach and Britain's opposition to a permanent occupation of the Rhineland. Demilitarisation required the fortifications to be dismantled, and the belts became two green belts of public park, finished in 1933; the university, closed in 1798, was refounded in 1919.

Local elections on 13 March 1933 gave the Nazi Party 39.6 per cent of the vote, ahead of the Catholic Zentrum on 28.3, the Social Democrats on 13.2 and the Communists on 11.1. The next day Nazi followers occupied the city hall and took over the government, Communist and Social Democrat members of the city assembly were imprisoned and Mayor Adenauer was dismissed. The Jewish population was about 20,000 when the Nazis came to power. By 1939, 40 per cent of the city's Jews had emigrated, and the great majority of those who stayed had been deported to concentration camps by 1941. The trade fair grounds beside the Deutz railway station were used to herd the Jewish population together for deportation to the death camps and to dispose of their household goods by public sale. On Kristallnacht in 1938 the city's synagogues were desecrated or set on fire. Essentially all of the pre-war Jewish population of 11,000 was deported or killed and all six synagogues were destroyed; the synagogue on Roonstraße was rebuilt in 1959. On 10 November 1944 a dozen members of the anti-Nazi Ehrenfeld Group were hanged in public, six of them sixteen-year-old boys of the Edelweiss Pirates, among them Barthel Schink.

On the night of 30 to 31 May 1942 Cologne was the target of Operation Millennium, the first thousand-bomber raid of the war: more than a thousand heavy bombers dropped some 1,455 tons of explosive, two thirds of it incendiary, in about seventy-five minutes. The reported death toll is between 469 and 486, around nine tenths of them civilians, with more than 5,000 injured and tens of thousands made homeless. In all the Allies flew 262 raids against Cologne and dropped 44,923.2 tons of bombs, destroying 61 per cent of the built-up area and almost the whole centre, and causing about 20,000 civilian deaths. By May 1945 only 20,000 residents remained of a 1939 population of more than 770,000, most of the loss through evacuation. American troops took the inner city on the left bank in half a day on 6 March 1945; because retreating German engineers had destroyed the Hohenzollern bridge, the boroughs on the right bank stayed under German control until mid-April.

In 1945 the architect and planner Rudolf Schwarz called Cologne the world's greatest heap of rubble; his 1947 master plan cut new thoroughfares through the centre while most downtown lots lay empty. Rebuilding the twelve Romanesque churches, among them St Gereon and Great St Martin, was disputed at the time, but the work went ahead and ran into the 1990s, finishing with St Kunibert. With Düsseldorf made political capital of North Rhine-Westphalia and Bonn the provisional federal capital, Cologne took in a large number of federal agencies. Its population regained pre-war numbers in 1959 and passed a million for about a year from 1975 and again from 2010, making it the fourth largest city in Germany. On 3 March 2009 the building of the Cologne city archive, which held the city's records since the Middle Ages, collapsed during construction of an underground railway extension.