In the 14th century, it was already an important trade center. In 1376, the craftsmen were divided in 19 guilds. Sibiu became the most important ethnic German city among the seven cities that gave Transylvania its German name Siebenbürgen (literally seven cities), and it was home to the Universitas Saxorum, the assembly of Germans in Transylvania. Common opinion in the 17th century ascribed Sibiu the quality of being the easternmost city to be part of the European sphere; it was also the eastern terminus of postal routes.
During the 18th and 19th centuries, the city became the second and later the first most important center of Transylvanian Romanian ethnics. The first Romanian-owned bank had its headquarters here (The Albina Bank), as did the ASTRA (Transylvanian Association for Romanian Literature and Romanian's People Culture). After the Romanian Orthodox Church was granted status in the Habsburg Empire from the 1860s onwards, Sibiu became the Metropolitan seat, and the city is still regarded as the third most important center of the Romanian Orthodox Church. Between the 1848 Hungarian Revolution and 1867 (the year of the Ausgleich), Sibiu was the meeting-place of the Transylvanian Diet, which had taken its most representative form after the Empire agreed to extend voting rights in the region.
After World War I, when Austria-Hungary was dissolved, Sibiu became part of Romania; the majority of its population was still ethnic German (until 1941) and counted large Romanian and Hungarian communities. Starting from the 1950s and until after 1990, most of the city's ethnic Germans emigrated to Germany. Among the roughly 2,000 who have remained is Klaus Johannis, who is currently mayor of Sibiu City.

http://en.wikipedia.org/wiki/Sibiu