Backstory to Philemon

The story behind the letter to Philemon takes place in the town of Colossae.
Broad_overview_of_geography_relevant_to_

Paul is probably under arrest in Rome. The church in Colossae meet​s in the home of Philemon, a wealthy landowner who owned servants/slaves. One of his slaves, Onesimus, ran away, found Paul, became a Christian, and is now returning to Colossae and to Philemon with the letter from Paul. I can only imagine the apprehension he must have felt as he made this trip back home.