Roman Military Oath of Allegiance

The Roman Military Oath of Allegiance, called the Sacramentum Militare, was an oath that pledged complete loyalty to the Roman Emperor. It was sworn by all new recruits to the Legion.
Under the Roman Republic it was sworn to the Consul. The Gladiators also pledged an oath of loyalty.

From around the reign of Severus Alexander (222-235 CE) it became an Oath sworn annually on the 3rd of January.
In Roman Law, the Oath of allegiance had a religious significance. To break this Oath, was to break the Law.
Therefore, the Punishment for disobedience was either Corporal Punishment or Execution.
Christian soldiers were faced with a dilemma, as Baptism was the only Sacrament they were permitted.
Little has changed in 2,000 years as today, all modern armies require new recruits to pledge an oath of allegiance.

Urant autem milites omnia se strenue facturos quae praeceperit imperator, numquam deserturos militiam nec mortem recusaturos pro Romana republica
‘The soldiers swear to faifhfully execute all the Emperor’s commands, never to desert the service, and never to avoid dying for the Roman Republic!’

The Gladiators also swore an Oath of Allegiance, the Sacramentum Gladiatorum, the ‘Oath of the Gladiator’:
‘uri, vinciti, verberari, ferroque necari’ meaning, ‘I will abide to be burnt, bound, beaten and killed by the sword’.