Commodus was born in 161, in Lanuvium, near Rome, to emperor Marcus Aurelius and Faustina the Younger. He had an elder twin brother, Titus Aurelius Fulvus Antoninus, who died in 165. In 176, Commodus was granted by his father the rank of Imperator and from 177, Marcus Aurelius decided to share the throne of Rome with his son, which was a big mistake. In 178, Commodus married Bruttia Crispina, who was the daughter of Gaius Bruttius. He accompanied his father to the Danubian front once more in 178, where Marcus Aurelius died on March 17, 180, leaving the 19-year-old Commodus sole emperor.

Commodus had a weak character as he was easily influenced by others. He was prone to cruelty and excessive behavior, which was held in check when his father was still alive. But once Marcus Aurelius had died, Commodus behaved like a new Nero. Commodus’ accession to power marked the end of a period of 80 years in Roman history which had brought men to the throne by merit rather than by birth.

Although Marcus Aurelius was born in Rome in 121 AD, his family had originated in Ucubi, a small town southeast of Córdoba in Iberian Baetica, Spain. When he was young, Marcus learned Greek philosophy and was trained in oratory. In 161, he was adopted by Roman Emperor Antoninus Pius. That year, at the age of 40, Marcus Aurelius ascended the throne and shared his imperial power with his adopted brother Lucius Aurelius Verus. When he became a sole ruler, Marcus spent most of his reign waging wars against rebellious Parthians, Germanic tribes and Britons on the empire’s frontier, but he was also known to be a humane ruler.

In 175 AD, Marcus Aurelius was faced with a revolt stirred up by Avidius Cassius, the governor of Syria, who believed rumors that the Emperor had died. After the rebellion was crushed, Cassius’s head was sent to Marcus Aurelius. According to some sources, Faustina, Marcus’ wife, may have been involved in this conspiracy. An epidemic of plague followed Cassius’s army from the East and thousands of people died. Year after year Aurelius tried to push barbarians back but witnessed the gradual crumbling of the Roman frontiers. In these times of disasters, he turned more and more to the study of Stoic philosophy. In 177 AD, towards the end of his reign, Marcus Aurelius admitted his own son, Commodus, to participation in the government, which was a big mistake.

Antoninus Pius was born on September 19, 86 AD, at Lanuvium, about 20 miles south of Rome. His father was Titus Aurelius Fulvus, who was consul in 89 whose family had come from Nemausus, and his mother was Arria Fadilla. Antoninus’ father and paternal grandfather died when he was young and he was raised by Gnaeus Arrius Antoninus, who was his grandfather on his mother’s side. Gnaeus Arrius Antoninus was a man of integrity and culture and a friend of Pliny the Younger. Long before he took the throne of Rome, between 110 AD and 115 AD, Antoninus Pius married Annia Galeria Faustina the Elder. They had a very happy marriage. She was the daughter of consul Marcus Annius Verus and Rupilia Faustina. Faustina was a beautiful woman, who was renowned for her wisdom. She spent her whole life caring for the poor and assisting the most disadvantaged Romans.

At the age of 24 Antoninus became quaestor, and then was raise to the rank of praetor. In 120 AD he obtained the consulship; he was next appointed by the Emperor Hadrian as one of the four proconsuls to administer Italia, then greatly increased his reputation by his conduct as proconsul of Asia. He acquired much favor with the Emperor Hadrian, who adopted him as his son and successor in 138 AD, after the death of his first adopted son Lucius Aelius, on the condition that Antoninus would in turn adopt Marcus Annius Verus.

His reign was the most peaceful in the entire history of the Roman Empire. While there were several military disturbances throughout the Empire in his time, in Mauretania, Judaea, and among the Brigantes in Britannia, none of them were serious. Southern Scotland was conquered, with Hadrian’s wall being abandoned and a new defence, the Antonine Wall, was built 40 miles further north.