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).

Philadelphiassa Ammia ja Quadratus olivat kristittyjä profeettoja, jotka palvelevat Philadelphiassa Hadrianuksen hallituskauden aikana. Montanistinen liike, joka alkoi 2C: n lopulla, sai alkunsa 10 km itään Philadelphiasta Ardabavissa.