→ Main article: History of the city of Salzburg
Early history and Bavarian times
The area of the town has been continuously settled since the Neolithic Age until today. In the La Tène period it was an administrative centre of the Celtic alums in the Kingdom of Noricum. The population on the city hills was moved to the area of the old town after the Roman invasion in 15 BC, in accordance with Roman town planning. The new city was one of the most important cities of the now Roman province of Noricum since Emperor Claudius as Municipium Claudium Iuvavum. After the abandonment of the province of Noricum in 488 at the beginning of the Migration Period, part of the Romano-Celtic population remained in the country. In the 6th century, the land was taken over by the Bavarians. Bishop Rupert received the remains of the Roman city as a gift from Duke Theodo II of Bavaria around 696 AD in order to missionize the country in the east and southeast. He renewed the monastery of St. Peter and founded the Benedictine nunnery of Nonnberg. The province of Salzburg and its counties soon gained more and more influence and power within Bavaria due to the flourishing salt mining and the extensive missionary activities.
In 996, Emperor Otto III granted Salzburg the right to hold markets, mint coins and tolls, and in 1120/30 a town judge was already mentioned in a document. The oldest known town charter dates back to 1287.
Prince-Archbishop's residential town
Since the Battle of Mühldorf in 1322, the archbishopric was at enmity with the motherland Bavaria. As a result, Salzburg became an independent archdiocese within the Roman-German Empire. The economic prosperity of the city in the 15th century led to a self-confident middle class with increasing rights and duties. Archbishop Leonhard von Keutschach, who was economically very successful, ended this autonomy by force. A few years after Martin Luther's posting of the theses, the majority of the city's population was close to Protestantism, and the unbending Protestants were then all expelled from the country by 1590. Criticism of the archbishop's authoritarian power continued to grow under Keutschach. In 1525, rebellious squires and peasants laid siege to the fortress of Hohensalzburg, where Archbishop Matthäus Lang von Wellenburg had entrenched himself. Only with the help of troops bought from the Swabian League were the rebels forced to retreat. Around 1600, the archbishopric was one of the richest principalities in the Roman-German Empire due to salt and gold mining. At that time Archbishop Wolf Dietrich von Raitenau redesigned the old town centre. The large late Romanesque cathedral was demolished and rebuilt by Markus Sittikus in early Baroque style.
Paris von Lodron succeeded in keeping Salzburg out of the Thirty Years' War (1618-1648) through a clever policy of neutrality. The city was developed into one of the best fortified cities in Europe. (See also article Fortifications of the City of Salzburg).
Salzburg soon became a centre of the Counter-Reformation, where monasteries, a seminary and numerous baroque churches were built, and a large part of the inhabitants were united in lay brotherhoods. In the years between 1675 and 1690, the Zauberbuben trials took place in Salzburg, as a result of which over 150 people were executed for alleged witchcraft. The majority of them were boys and youths.
In 1732, under Archbishop Leopold Anton von Firmian, the majority of the Protestants remaining in the country were forced to emigrate (Salzburg exiles).
Under Archbishop Hieronymus Franz Josef Colloredo of Wallsee and Mels, Salzburg became a centre of the late Enlightenment between 1772 and 1800, where science and the arts flourished.
part of Austria
In 1803, by order of Napoleon Bonaparte, Salzburg became a secularized electorate, and in 1805, together with Berchtesgaden, it was annexed to the new Empire of Austria, and in 1810 it was again annexed to the Kingdom of Bavaria. In 1800, 1805 and again in 1809 Salzburg was occupied and plundered by Napoleonic troops.
In 1816, with the Treaty of Munich, most of the province of Salzburg again fell to the Empire of Austria and thus under Habsburg rule. At first Salzburg was a district town of little importance in the crown land of Upper Austria, to which, apart from a few spa guests, only a few painters and literary figures strayed. These, however, were enchanted by the beauty of the city and their reports made Salzburg more and more a tourist destination. On April 30, 1818, a fire broke out that raged through the city for four days. Around a hundred houses were destroyed. In 1860 the demolition of the city fortifications began, they were mainly used as building material for the new Salzach slaughter. In the same year the people of Salzburg celebrated the opening of the railway lines Vienna - Salzburg and Salzburg - Munich. This ensured strong growth of the city and allowed trade and commerce to flourish.
The end of the First World War also brought a period of hunger to Salzburg, and the economy recovered only gradually.
In the period between 1935 and 1939 various neighbouring villages were incorporated. During the Nazi regime, arrests and deportations of political opponents as well as Jews and other minorities took place from 1938 onwards. Prisoners of war kept the economic life going. In 1944/45 aerial bombs from the USA damaged large parts of the town. Colonel Hans Lepperdinger saved the city in 1945 by refusing to obey orders and handing it over to the US without a fight. Salzburg was the seat of the US High Command after the end of the war. In the first post-war years the city was marked by the misery of the refugees. Only gradually were the barrack dwellings replaced by the construction of new districts. In 1962 the university, which had been dissolved in 1810, was re-established. In the following period Salzburg became an economically successful trade, fair and tourism city.
The development of the city of Salzburg, shown as a time series of 30 years each
· Detailed historical plans of the city
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The graph on the right shows the increasing decoupling of built-up area and the respective number of inhabitants after about 1970. Despite a hardly increasing number of inhabitants, the demand for space for new buildings continues to grow strongly (also) in the city of Salzburg. (Data: respective sum of built-up areas and adoption of the respective number of inhabitants)