Ephesus was the capital of Roman province of Asia.  At Ephesus Jesus pronounced a discourse on the soul for a local thinker. 
Paul resided two years in Ephesus making tents for a living and conducting lectures on religion and philosophy each night in the main audience chamber of the school of Tyrannus.  Apostle John settled in Ephesus and there he became an aged bishop. 
See also: UB 130:0.3.