An optio sometimes anglicized option (though rarely, to avoid confusion with "option"), was a soldier in the Roman army

Roman army

The Roman army is the generic term for the terrestrial armed forces deployed by the kingdom of Rome , the Roman Republic , the Roman Empire and its successor, the Byzantine empire...

 who held a position similar to that of an executive officer

Executive officer

An executive officer is generally a person responsible for running an organization, although the exact nature of the role varies depending on the organization.-Administrative law:...

 in modern armies. The optio seems to have held a rank roughly equivalent to that of a modern lieutenant

Lieutenant

A lieutenant is a junior commissioned officer in many nations' armed forces. Typically, the rank of lieutenant in naval usage, while still a junior officer rank, is senior to the army rank...

, reflective of his status as the second in command of the century in which he served. The main function of an optio was as an optio centuriae, the second-in-command of a century

Centuria

Centuria is a Latin substantive from the stem centum , denoting units consisting of 100 men. It also denotes a Roman unit of land area: 1 centuria = 100 heredia...

, although there were many other positions an optio could hold.

Optiones were vital units in the Roman army. An optio was stationed at the rear of the ranks to keep the troops in order. Their duties would include enforcing the orders of the centurion, taking over the centurion's command in battle should the need arise, supervising his subordinates, and a variety of administration duties.

Optio pay was double the standard legionary pay and they were the most likely men to be promoted after the retirement, promotion or death of a centurion.

Types of optio

Titles held by optiones included:

• Optio ad carcerem: chosen man on prison duty (incarceration
  Incarceration
  Incarceration is the detention of a person in prison, typically as punishment for a crime .People are most commonly incarcerated upon suspicion or conviction of committing a crime, and different jurisdictions have differing laws governing the function of incarceration within a larger system of...
  
  ).
• Optio ad spem ordinis: optio being groomed for promotion to the rank of centurion.
• Optio candidatus: optio being groomed for promotion to the rank of centurion.
• Optio carceris: soldier in charge of the prison cells.
• Optio centuriae: 'chosen man of the centuria; second-in-command and rear rank officer of a centuria; classed as a duplicarius, a soldier receiving double basic pay; he carried a hastile (wooden staff).
• Optio centurionis: 'chosen man of the centurion'; same as optio centuriae.
• Optio custodiarum: soldier in charge of guard posts.
• Optio draconarius: 'chosen man among the dragon bearers', a late Roman senior standard bearer.
• Optio equitum: optio in the legionary or Praetorian
  Praetorian Guard
  The Praetorian Guard was a force of bodyguards used by Roman Emperors. The title was already used during the Roman Republic for the guards of Roman generals, at least since the rise to prominence of the Scipio family around 275 BC...
  
   cavalry
  Cavalry
  Cavalry or horsemen were soldiers or warriors who fought mounted on horseback. Cavalry were historically the third oldest and the most mobile of the combat arms...
  
   (equus=horse).
• Optio fabricae: soldier in charge of a workshop.
• Optio navaliorum: soldier in charge of boats.
• Optio praetorii: soldier attached to headquarters.
• Optio principalis: optio who held supervisory rank (principales from the 2nd century onwards); not all who had the title of optio held this status.
• Optio speculatorum: optio in the elite cavalry bodyguards.
• Optio spei: optio being groomed for promotion to the rank of centurion.
• Optio statorum: optio of military police.
• Optio tribuni: assistant to a tribune
  Tribune
  Tribune was a title shared by elected officials in the Roman Republic. Tribunes had the power to convene the Plebeian Council and to act as its president, which also gave them the right to propose legislation before it. They were sacrosanct, in the sense that any assault on their person was...
  
  .
• Optio valetudinarii: orderly in charge of a hospital.

Uniform

Unlike the centurion, the uniform was not the distinguishing part of the optios uniform. The identifying part would be his helmet; this would have had plumes of horse hair or feathers on either side of his helmet that could be accompanied by a helmet crest.

An optios armour would be more like those of the common legionary. He could wear the lorica segmentata

Lorica segmentata

The lōrīca segmentāta was a type of segmented armour almost exclusively used in the Roman Empire, but the Latin name was first used in the 16th century...

 or a lorica hamata

Lorica hamata

The lorica hamata is a type of mail armour used by the Roman Republic and the Roman Empire. During the 1st century it was starting to be supplemented by lorica segmentata, but had been reintroduced as sole standard-issue armor by the 4th century. It was issued for both primary Legionary and...

 as well as have his gladius on the right not left side. One thing that did separate him from the common legionary was the staff (called a hastile), which was used to keep the legionaries in line. This staff would be roughly as tall of the optio himself. Optiones often carried wax tablets on which they kept the orders of the day.

Vegetius about Optiones

The Optiones are subaltern officers, so denominated from their being selected by the option of their superior officers, to do their duty as their substitutes or lieutenants in case of sickness or other accident. (Vegetius

Vegetius

Publius Flavius Vegetius Renatus, commonly referred to simply as Vegetius, was a writer of the Later Roman Empire. Nothing is known of his life or station beyond what he tells us in his two surviving works: Epitoma rei militaris , and the lesser-known Digesta Artis Mulomedicinae, a guide to...

. De Re Militari

De Re Militari

De Re Militari , also Epitoma Rei Militaris, is a treatise by the late Latin writer Vegetius about Roman warfare and military principles as a presentation of methods and practices in use during the height of Rome's power, and responsible for that power...

, II)