40 Martyrs of Sebaste
320
320
313 - Constantine enacts the Edict of Milan legalising Christianity within the Roman Empire.
Note this video includes considerable material beyond the story of he 40 Roman soldiers, including graphic images of ISIS persecution of Christians.
This is the same story but with some variation in the details.
40 Martyrs Of Sebaste - Dan Graves (Christianity.com)
40 Brave Soldiers For Jesus by Tom Green