Plovdiv city was possibly at times a vassal of Bulgaria or Venice. Ivan Asen II conquered the duchy finally in 1230 but the city had possibly been conquered earlier. Afterwards, Plovdiv was conquered by Byzantium. According to some information, by 1300 Plovdiv was a possession of Theodore Svetoslav of Bulgaria. It was conquered from Byzantium by George Terter II of Bulgaria in 1322. Andronikos III Palaiologos unsuccessfully besieged the city, but a treaty restored Byzantine rule once again in 1323. In 1344 the city and eight other cities were surrendered to Bulgaria by the regency for John V Palaiologos as the
History of Plovdiv 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 by the archbishop of Plovdiv Cyril who later became Bulgarian Patriarch. During the period of communist governance that followed the end of World War II many large factories were built in and nearby Plovdiv, for example a plant for non-ferrous metals, textile works,