The Slavs had settled in the area by the middle of the 6th century, changing the ethnic proportions of the region. With the establishment of
Bulgaria in 681, Philipopolis became a border fortress of the
Byzantine Empire. It was captured by Khan
Krum in 812, but the region was incorporated into the
Bulgarian Empire in 834 during the reign of Khan
Malamir. It remained in Bulgarian hands until it was conquered by the
Byzantine Empire in 970 or 971. The city again came to be known as Philippopolis and became Byzantine in character. Aime de Varennes in 1180 encountered the singing of Byzantine songs in the city that recounted the deeds of Alexander the great and his predecessors, over 1,300 years before.
Krum was the first Bulgarian ruler to capture Plovdiv. Byzantine rule was succeeded by the
Latin Empire in 1204, and there were two short interregnum periods as the city was twice occupied by
Kaloyan of Bulgaria before his death in 1207. In 1208 Kaloyan's successor
Boril was defeated by the Latins in the
Battle of Philippopolis. Under Latin rule, Plovdiv was the capital of the
Duchy of Philippopolis governed by
Renier de Trit, and later on by Gerard de Strem. Bulgarian rule was reestablished during the reign of
Ivan Asen II between 1225 and 1229. In 1263 Plovdiv was conquered by the restored
Byzantine Empire and remained in Byzantine hands until it was re-conquered by
George Terter II of Bulgaria in 1322. Byzantine rule was restored once again in 1323, but in 1344 the city was surrendered to Bulgaria by the regency for
John V Palaiologos as the price for
Ivan Alexander of Bulgaria's support in the Byzantine civil war. In 1364 the
Ottoman Turks under Lala Shakhin Pasha seized Plovdiv. The Turks called the city
Filibe. It was the capital of Rumelia until 1382 when the Ottomans captured
Sofia, which became the main city of the province. Plovdiv survived as one of the major cultural centers for Bulgarian culture and tradition. The name
Plovdiv first appeared around that time and is derived from the city's Thracian name
Pulpudeva (assumed to be a translation of Philippopolis, from Pulpu = Philippou and deva = city), which was rendered by the Slavs first as
Pəldin (
Пълдин) or
Pləvdin. ==National revival==