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 is the second or the third-largest cosmopolitan city inhabited by Bulgarians, after Sofia and possibly Varna. According to the 2001 census, out of a population of 338,224 inhabitants, the Bulgarians numbered 302,858 (90%). Stolipinovo in Plovdiv is the largest Roma neighbourhood in the Balkans, having a population of around 20,000 alone; further Roma ghettos are Hadji Hassan Mahala and Sheker Mahala. Therefore, the census number is a deflation of the number of Roma people, and they are most likely the second-largest group after the Bulgarians, most of all because the Muslim Roma in Plovdiv claim to be of Turkish ethnicity