Plovdiv city was originally a Thracian settlement and subsequently was invaded by Persians, Greeks, Celts, Romans, Goths, Huns, Bulgars, Slavs, Rus people, Crusaders, and Turks. On 4 January 1878, Plovdiv was liberated from Ottoman rule by the Russian army. It remained within the borders of Bulgaria until July of the same year, when it became the capital of the autonomous Ottoman region of Eastern Rumelia. In 1885, Plovdiv and Eastern Rumelia joined Bulgaria. Plovdiv is situated in a fertile region of south-central Bulgaria on the two banks of the Maritsa River. The city has historically developed on seven syenite hills, some
Plovdiv was inaugurated in the city. In the beginning of the 20th century, Plovdiv grew as a significant industrial and commercial center with well-developed light and food industry. In 1927 the electrification of Plovdiv has started. German, French, and Belgian capital was invested in the city in development of modern trade, banking, and industry. In 1939 there were 16,000 craftsmen and 17,000 workers in manufacturing factories, mainly for food and tobacco processing. During the Second World War, the tobacco industry expanded as well as the export of fruit and vegetables. In 1943, 1,500 Jews were saved from deportation in concentration camps