It is an independent city located in the centre of the district of Rosenheim (Upper Bavaria), and is also the seat of its administration.

Rosenheim is situated in the Upper-Bavarian Alpine Foothills, 450 metres (1,476 feet) above sea level and covers an area of 37.52 square kilometres (14.49 sq mi).

Even today in many places around the city the former shoreline can be recognised where the former flat lake bed changes suddenly into relatively steep embankment.

It subsequently evolved from a market to a salt trade and then railway town to today's wood and college city.

The intersection of these two enormously important trade routes were protected by a military station whose name was "Pons Aeni".

Pons was between Aeni Isinisca (Aying) and Bedaium [de] (today part of Seeon-Seebruck), as shown on the Roman road map Tabula Peutingeriana from the 4th century.

Possibly,the name comes from the Rosenheim Rose emblem of the Wasserburger Earl Hall, who built the castle.

Another theory is that the name Ross derives from the Rössern steeds that were used in medieval times to pull the river transport vessels, and for which there were large stables in Rosenheim.

The street names Am Esbaum (the tree on which the horses were grazing) or Am Roßacker add some weight to this suggestion.

The area around the Inn Bridge was not developed for a long time due to marshy soil at the proximity of the mouth of the river Mangfall, so the settlement was located several hundred meters away.

Until about 1600 the settlement had grown into one of the largest and most important markets in Bavaria, even though town privileges were only attained in 1864 from the Bavarian King Ludwig II.

In the 19th century Rosenheim developed as an economic centre in the Southeast of Bavaria due to brine.

In 1810 an early type of wooden pipeline brought brine from the Reichenhall and Traunstein salt mines to Rosenheim.

The old station is directly opposite the 1878 City Hall and is used in the ZDF evening series "Die Rosenheim-Cops" as the police headquarters backdrop.

At the beginning of the 20th century, Rosenheim had nine breweries which are preserved in the names of some restaurants (Duschl-, Hof-, Mail-, Pernloher-, Stern-, Weißbräu).

A request was made to the city council for establishment of a separate Jewish religious association, with reference to the Bavarian-Jewish legislation, but it was refused, so the Rosenheim Jews remained attached to the state capital, where their dead also had to be buried.

Even the funeral of the First World War fallen son of a Jewish merchant based in Rosenheim at the city cemetery was refused and was "the biggest disappointment and the bitterest pain" for the father.

With the creation of the first local Nazi group outside of Munich in 1920, the Rosenheim Jews saw increasing hostility.

The college of the city of Rosenheim, on 29 July 1920 came to the conclusion that ... es sei bedauerlich, dass die Bewegung zur Bekämpfung eines volksausbeuterischen Judentums [...], die in ihrem Wesen gewiß berechtigt sei, durch solche Auswüchse in Mißkredit komme."...

On 1 April 1933, shortly after the Nazi seizure of power, guards were set up in front of Jewish shops, warning against buying in these stores but to desist assault and criminal damage.

The assassination of German diplomat Ernst vom Rath by the Polish Jewish teenager Herschel Grynszpan on 7 November 1938 in Paris was taken as the pretext for Kristallnacht, a final opportunity to strike against the Jews.

The SA came with 8 to 10 men on 10 November at 3–4 o'clock in the morning to the last two Jewish shops, and destroyed their inventory and merchandise.

The first air attack was on 20 October 1944 at lunch time from 12:47 to 13:17, with over a hundred aircraft dropping ~1,000 bombs, leaving 27 dead and 59 wounded.

The Kultur- und Kongresszentrum Rosenheim (KU'KO) (Culture and Congress Centre) was built on the site of the brine works, demolished in 1967.

With many original objects, the museum displays the Inn Shipping Company, the source of Rosenheim's prosperity in the Middle Ages, in the past centuries.

Over 400 square meters of exhibition space this unique museum displays wood as a raw material, its importance and processing past and present, which is closely related to the timber town of Rosenheim and its training centres for wood occupations.

After the great fire in 1641 the Rosenheim onion dome was built and later extended into a long building.

On the façade facing the square is the emblem of Louis Rosenheim, with the white rose against a red background.

At the end of the 19th century he obtained a relatively large area of land for its day, and built 15 houses, including the Hotel Deutscher Kaiser.

The Kunstwiese shows three-dimensional contemporary art works by artists from Rosenheim all year round.