Diadumenian (Latin: Marcvs Opellivs Antoninvs Diadvmenianvs Avgvstvs) (14/19 September 208 – 218), was the son of the Roman Emperor Macrinus, and served his father briefly as Caesar (May 217–218) and as Augustus (in 218).

Diadumenian was born on the 14th of September 208 or, according to Historia Augusta, on the 19th of September because he shared the same birthday with the Emperor Antoninus Pius. His mother was Empress Nonia Celsa, although little is known of her: she is only mentioned by the Historia Augusta. He was born Marcus Opellius Diadumenianus, but his name was changed and added Antoninus to solidify connection to the family of Marcus Aurelius as done by Caracalla.

Diadumenian had little time to enjoy his position or to learn anything from its opportunities because the legions of Syria revolted and declared Elagabalus ruler of the Roman Empire. When Macrinus was defeated on 8 June 218, at Antioch, Diadumenian's death followed his father's.

Marcus Aurelius (Latin: Marcus Aurelius Antoninus Augustus; 26 April 121 – 17 March 180 AD), was Roman Emperor from 161 to 180 AD. He ruled with Lucius Verus as co-emperor from 161 until Verus' death in 169. He was the last of the "Five Good Emperors", and is also considered one of the most important Stoic philosophers. During his reign, the Empire defeated a revitalized Parthian Empire; Aurelius' general Avidius Cassius sacked the capital Ctesiphon in 164. Aurelius fought the Marcomanni, Quadi, and Sarmatians with success during the Marcomannic Wars, but the threat of the Germanic tribes began to represent a troubling reality for the Empire. A revolt in the East led by Avidius Cassius failed to gain momentum and was suppressed immediately.

Marcus Aurelius' Stoic tome Meditations, written in Greek while on campaign between 170 and 180, is still revered as a literary monument to a philosophy of service and duty, describing how to find and preserve equanimity in the midst of conflict by following nature as a source of guidance and inspiration.

Mark Antony (Latin: M·ANTONIVS·M·F·M·N) (January 14, 83 BC – August 1, 30 BC) was a Roman politician and general. As a military commander and administrator, he was an important supporter and loyal friend of his mother's cousin Julius Caesar. After Caesar's assassination, Antony formed an official political alliance with Octavian (the future Augustus) and Lepidus, known to historians today as the Second Triumvirate.

The triumvirate broke up in 33 BC. Disagreement between Octavian and Antony erupted into civil war, the final war of the Roman Republic, in 31 BC. Antony was defeated by Octavian at the naval Battle of Actium, and in a brief land battle at Alexandria. He and his lover Cleopatra committed suicide shortly thereafter. His career and defeat are significant in Rome's transformation from Republic to Empire.

A member of the Antonia clan (gens), Antony was born on January 14, 83 BC. He was the homonymous and thus presumably the eldest son of Marcus Antonius Creticus (praetor 74 BC, proconsul 73–71 BC) and grandson of the noted orator Marcus Antonius (consul 99 BC, censor 97–6 BC) who had been murdered during the Marian Terror of the winter of 87–6 BC.