The oldest writings of St. Ignatius that were known to have existed and made use of by the historian Eusebius in the middle of the fourth century unfortunately no longer exist but were written on his jourey to rome to the early christians.
of Ephesus (Pros Ephesious);
of Magnesia (Magnesieusin);
of Tralles (Trallianois);
of Rome (Pros Romaious);
of Philadelphia (Philadelpheusin);
of Smyrna (Smyrnaiois); and
to Polycarp (Pros Polykarpon).
Then there are a fe writings that claim to be written by Ignatius but are typically said not to be written by him and these are as follows:
to Mary of Cassobola (Pros Marian Kassoboliten);
to the Tarsians (Pros tous en tarso);
to the Philippians (Pros Philippesious);
to the Antiochenes (Pros Antiocheis);
to Hero a deacon of Antioch (Pros Erona diakonon Antiocheias). Associated with the foregoing is
a letter from Mary of Cassobola to Ignatius.
4 Fide et Gratia February 2016