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).

Filadelfia Ammia e Quadratus erano profeti cristiani che ministravano a Filadelfia durante il regno di Adriano. Il movimento montanista, che iniziò alla fine del 2C, ebbe le sue origini a 10 km a est di Filadelfia ad Ardabav. Con le sue due profetesse Prisca e Maximilla, Montanus insegnò che Paraclete (Lo Spirito Santo) sarebbe venuto poco prima del secondo avvento.