Who ruled Cologne?

Cologne stands on the left bank of the Rhine in western Germany, where the river leaves the hills and enters the lowland plain. The Romans founded it as a frontier city on this broad, navigable stretch of the Rhine, and its name still comes from the Latin word colonia. Through the Middle Ages it was the largest city in the German lands, a great centre of pilgrimage and trade ruled first by powerful archbishops and then by its own merchants. Its twin-spired cathedral, begun in 1248 and finished in 1880, came through the Second World War standing above a city almost entirely in ruins.

The Romans resettled the Germanic Ubii people on the west bank of the Rhine in the late 1st century BCE, and their town became an important base on the frontier of the Roman Empire. Agrippina the Younger, who later married her uncle, the Emperor Claudius, was born there, and in 50 CE the town was raised to the rank of a colonia named Colonia Claudia Ara Agrippinensium in her honour. Later in the century it became the capital of the province of Lower Germany, with a governor's palace, walls and an aqueduct, and in the 260s it briefly served as capital of the breakaway Gallic Empire. A Christian bishop, Maternus, is recorded in 313.

In the mid 5th century the Franks took the city, and it passed into the Frankish kingdom. Under Charlemagne its bishop Hildebold became an archbishop, and his successors grew into great territorial princes and, later, electors of the Holy Roman Empire. In 1164 Archbishop Rainald of Dassel, chancellor to Frederick Barbarossa, brought relics believed to be those of the Three Magi from conquered Milan. They made Cologne one of the main pilgrimage centres of Europe and were the reason for the vast Gothic cathedral started in 1248.

By around 1200 the city had about 40,000 people, comparable in size to London or Paris, and its merchants traded from England and Flanders to the Baltic as members of the Hanseatic League. The citizens repeatedly fought their archbishop. After the city's side won the Battle of Worringen in 1288, the archbishops lived mostly outside the city, at Bonn, and in 1475 Cologne was formally recognised as a Free Imperial City. A city-run university opened in 1388. The Jewish community, one of the oldest in Germany, was massacred during the Black Death in 1349 and expelled in 1424.

Building work on the cathedral stopped in the 15th century, and the city stagnated after the Thirty Years' War. French revolutionary troops occupied it in 1794 and it was annexed to France, then given to the Kingdom of Prussia in 1815. Under Prussia the cathedral was finally completed, as a symbol of German national feeling, and railways and industry made Cologne a major commercial city. Konrad Adenauer served as its mayor from 1917 until the Nazis removed him in 1933.

The Second World War devastated Cologne. The Royal Air Force sent its first thousand-bomber raid against it in May 1942, and by 1945 most of the city was destroyed and a population of more than 770,000 in 1939 had shrunk to a small fraction. The Jews who had not emigrated were deported and murdered. Rebuilding began under British occupation, and Adenauer, briefly restored as mayor, went on to become the first chancellor of West Germany in 1949. Today Cologne has just over a million inhabitants, making it Germany's fourth-largest city and a centre of media, trade fairs and the Rhineland's carnival.