St. Mark wrote his Gospel for Roman Gentile Christians around AD 55-61. It is the earliest Gospel and was written based on St. Peter's teachings. St. Mark served with St. Paul and St. Barnabas, preaching in various regions. He helped establish the church in Rome. St. Mark was martyred in Alexandria after being dragged through the streets. His Gospel provides essential details about Jesus' life and ministry and is written for non-Jews, explaining Jewish customs and translating Aramaic phrases.