Who was St. Matthew?

Matthew Levi was a tax collector 'sitting at the receipt of custom' in Capernaum. By definition he was a Roman agent, appointed ultimately by Pontius Pilate.
The Romans faced Jewish uprisings every ten or twenty years in their Occupation of Palestine.
It was very risky for Jesus to invite Matthew, or to allow him, to become a disciple.
After Jesus led a failed uprising, trying to take over the Temple in Jerusalem at Passover, he was executed along with two Zealot leaders.
The Romans seem to have been fully prepared for the event. Presumably they had someone on the inside of Jesus' movement.
After Jesus' execution, the movement had no clear leadership and began to disintegrate. Matthew hung around long enough to observe this, and then disappears from the record.
He apparently told people he was going to "Ethiopia, south of the Caspian Sea". Ha ha, very funny.

ABNA 2009 Review of 'The Gospel According to the Roman Occupation'

ABNA 2009: "The Gospel According to the Romans" made it to the Quarterfinals.

Here is one of the professional reviews:

"This is exceptionally erudite, flawless, and subversively delicious. The author blends an almost vicious comedy to some serious history for a compelling historical fiction. The characters are richly drawn, the narrative fierce, muscular, compelling. The author has mastery of prose and story and knows how to mold the English language into an empire of a story. The action and dialogue move the story forward as well as develop the characters. The setting is atmospheric with the era pitch perfect. This is a story I would like to read in full."