Ephesians is an epistle written by Paul when he was jailed in Rome. He met Epaphras and Onesimus and heard the news about the Colossian church [Colossians 1:7, 4:9]. 

At that time he wrote many letters and sent them to the Church in Asia. Although Paul was in prison at that time, his spiritual labor continued as he wrote the "Prison Epistles", including this letter.

The church of Ephesus had deep fellowship with such servants of God at that time as the Apostle Paul, John, Mark, Timothy, Priscilla and Aquila. Timothy, Paul's spiritual son had stayed at the church of Ephesus at Paul's request and nurtured its flock with the Word. [1 Timothy 1:3].