Crete was located in the Mediterranean, south of the Aegean Sea. It was an important location for travel and trade by sea, so it had a mix of influences, including a Jewish population. Some from Crete had been at Pentecost (Acts 2:11), but this letter seems to deal with a church in the early stages of development.
elders in every town: There may have been more than one house church in a given town and possibly more than one elder in a given house church. Clearly, there were churches in at least two towns and the leadership was specific to each town.