From the LCMS website:

Born at the beginning of the second century, Justin was raised in a pagan family. He was student of philosophy who converted to the Christian faith and became a teacher in Ephesus and Rome. After refusing to make pagan sacrifices, he was arrested, tried and executed, along with six other believers. The official Roman court proceedings of his trial before Rusticius, a Roman prelate, document his confession of faith. The account of his martyrdom became a source of great encouragement to the early Christian community. Much of what we know of early liturgical practice comes from Justin.