Philadelphia was founded by the Pergamene king Attalus II (159-138 BC), which is the newest of the Seven Churches’ cities. When the Romans attempted to turn Attalus against his brother Eumenes II, he remained loyal, thereby earning the nickname “Philadelphus” (Polybus 30:1-3; 31.1; 32.1). The name of the city reflects the love between these brothers. Philadephia was strategically situated along the imperial post road that ran from Rome through Troas, Pergamum, and Sardis through to Tarsus and the east. Another road running eastward was an “open door” to Phrygia (Revelation 3:8).

Philadelphia Ammia en Quadratus waren christelijke profeten die in Filadelfia dienden tijdens de heerschappij van Hadrianus.De Montanistische beweging, die begon in het einde van 2C, had zijn oorsprong 10 km ten oosten van Philadelphia bij Ardabav. Met zijn twee profeten Prisca en Maximilla, Montanus onderwees dat Paraclete (Heilige Geest) zou komen net voor de tweede komst.