Ephesus was a major port at the mouth of the Cayster River in western Asia Minor. It was an important commercial, cultural, and religious center. The temple to the goddess Artemis in Ephesus was one of the seven wonders of the ancient world.
Paul came to Ephesus after founding a congregation in Corinth. He was accompanied by Priscilla and Aquila, who instructed a man named Apollos in the Christian faith at Ephesus (Acts 18:18-26). In Acts 19, a silversmith associated with the temple of Artemis foments a riot, claiming that Paul's preaching would lead many to scorn the cult of Artemis. No charges are brought, but Paul soon leaves Ephesus for Greece.