This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. February Learn how and when to remove this template message The Sterntor, originally built around , is a gate reconstructed on the remnants of the medieval city wall.
The history of the city dates back to Roman times. In about 12 BC, the Roman army appears to have stationed a small unit in what is presently the historical centre of the city. Even earlier, the army had resettled members of a Germanic tribal group allied with Rome, the Ubii , in Bonn. The Latin name for that settlement, "Bonna", may stem from the original population of this and many other settlements in the area, the Eburoni. The Eburoni were members of a large tribal coalition effectively wiped out during the final phase of Caesar 's War in Gaul.
After several decades, the army gave up the small camp linked to the Ubii-settlement. During the 1st century AD , the army then chose a site to the north of the emerging town in what is now the section of Bonn-Castell to build a large military installation dubbed Castra Bonnensis, i. Initially built from wood, the fort was eventually rebuilt in stone. With additions, changes and new construction, the fort remained in use by the army into the waning days of the Western Roman Empire , possibly the mid- 5th century.
The structures themselves remained standing well into the Middle Ages , when they were called the Bonnburg.
They were used by Frankish kings until they fell into disuse. Eventually, much of the building materials seem to have been re-used in the construction of Bonn's 13th-century city wall.
The Sterntor star gate in the city center is a reconstruction using the last remnants of the medieval city wall. To date, Bonn's Roman fort remains the largest fort of its type known from the ancient world , i.
The fort covered an area of approximately , square metres 62 acres. Between its walls it contained a dense grid of streets and a multitude of buildings, ranging from spacious headquarters and large officers' quarters to barracks , stables and a military jail.
Among the legions stationed in Bonn, the "1st", i. Units of the Bonn legion were deployed to theatres of war ranging from modern-day Algeria to what is now the Russian republic of Chechnya. The Altes Rathaus old town hall as seen from the central market square. It was built in in Rococo-style. Once past the South Gate, the Cologne—Mainz road continued along what are now streets named Belderberg, Adenauerallee et al. On both sides of the road, the local settlement, Bonna, grew into a sizeable Roman town.
Bonn is shown on the 4th century Peutinger Map. In late antiquity , much of the town seems to have been destroyed by marauding invaders. The remaining civilian population then took refuge inside the fort along with the remnants of the troops stationed here. During the final decades of Imperial rule, the troops were supplied by Franci chieftains employed by the Roman administration.
When the end came, these troops simply shifted their allegiances to the new barbarian rulers, the Kingdom of the Franks. From the fort, the Bonnburg, as well as from a new medieval settlement to the South centered around what later became the minster , grew the medieval city of Bonn. Between the 11th and 13th centuries, the Romanesque style Bonn Minster was built, and in Bonn became the seat of the Archdiocese of Cologne.
The city gained more influence and grew considerably. The city was subject to a major bombardment during the Siege of Bonn in The elector Clemens August ruled — ordered the construction of a series of Baroque buildings which still give the city its character.
Another memorable ruler was Max Franz ruled — , who founded the university and the spa quarter of Bad Godesberg. In addition he was a patron of the young Ludwig van Beethoven , who was born in Bonn in ; the elector financed the composer's first journey to Vienna. In , the city was seized by French troops, becoming a part of the First French Empire.
Administered within the Prussian Rhine Province , the city became part of the German Empire in during the Prussian-led unification of Germany. Bonn was of little relevance in these years. Following the advocacy of West Germany's first chancellor, Konrad Adenauer , a former Cologne Mayor and a native of that area, Bonn became the de facto capital, officially designated the "temporary seat of the Federal institutions," of the newly formed Federal Republic of Germany in However, the Bundestag, seated in Bonn's Bundeshaus , affirmed Berlin 's status as the German capital.
Bonn was chosen as the provisional capital and seat of government despite the fact that Frankfurt already had most of the required facilities and using Bonn was estimated to be 95 million DM more expensive than using Frankfurt.
However, Adenauer and other prominent politicians intended to make Berlin the capital of the reunified Germany, and felt that locating the capital in a major city like Frankfurt or Hamburg would imply a permanent capital and weaken support in West Germany for reunification.
Bonn's time as the capital of West Germany is commonly referred to as the Bonn Republic, in contrast to the Berlin Republic which followed reunification in Today it serves as the President's secondary residence.
German reunification in made Berlin the nominal capital of Germany again. This decision did not mandate that the republic's political institutions would also move. While some argued for the seat of government to move to Berlin, others advocated leaving it in Bonn — a situation roughly analogous to that of the Netherlands , where Amsterdam is the capital but the Hague is the seat of government.
Berlin's previous history as united Germany's capital was strongly connected with the German Empire , the Weimar Republic and more ominously with Nazi Germany. It was felt that a new peacefully united Germany should not be governed from a city connected to such overtones of war. Former chancellor Willy Brandt caused considerable offence to the Western Allies during the debate by stating that France wouldn't have kept the seat of government at Vichy after Liberation.
The heated debate that resulted was settled by the Bundestag Germany's parliament only on 20 June By a vote of —,  the Bundestag voted to move the seat of government to Berlin. The vote broke largely along regional lines, with legislators from the south and west favouring Bonn and legislators from the north and east voting for Berlin. Ultimately, the votes of the eastern German legislators tipped the balance in favour of Berlin. In recognition of its former status as German capital, it holds the name of Federal City German: Bonn currently shares the status of Germany's seat of government with Berlin, with the President , the Chancellor and many government ministries maintaining substantial presences in Bonn.
Over 8, of the 18, federal officials remain in Bonn.