The Pantheon, roofed with the most spectacular dome of antiquity, is built in Rome by Hadrian

Suetonius, librarian to Trajan and personal secretary to Hadrian, is well placed to research his racy Lives of the Caesars

The Sant'Angelo bridge in Rome, still standing today, is built for the emperor Hadrian by means of a coffer dam

The emperor Hadrian, with no children of his own, appoints a respected senator, Antoninus Pius, to succeed him

Marcus Aurelius, for long the designated heir, becomes emperor on the death of Antoninus Pius

The bronze equestrian statue of Marcus Aurelius, on the Capitol in Rome, begins a long European tradition of public sculpture

Marcus Aurelius is rare among emperors in writing twelve books of philosophical Meditations

Plotinus, moving from Alexandria to Rome, teaches the influential philosophy later known as Neo-Platonism

The Christians of Rome use the catacombs as tomb chambers, and decorate the walls with murals on New Testament themes

The emperor Aurelian, grateful for the apparent assistance of a Syrian sun god, establishes the cult of the Unconquered Sun - whose birthday is December 25

Diocletian, commanding an army near the Bosphorus in Thracia, is proclaimed emperor by his troops

Constantine's father, recently appoinnted Augustus in the west, dies at York and the young man is proclaimed Augustus in his place by the legions in Britain

Constantine, preparing for battle against a rival at the Milvian Bridge, orders his men to wear a Christian symbol, the Chi-Rho, on their shields

Constantine meets his co-emperor Licinius in Milan, and persuades him to follow a policy of encouraging the Christians

Constantine founds several churches in Rome, among them the first St Peter's

Constantine's new churches in Rome introduce an important element in church architecture, the transept

Roman mosaic is at its most lavish in the floors of Piazza Armerina, in central Sicily

Constantine executes Licinius in Thessalonica on a charge of attempted rebellion, a year after defeating him in battle

St Ambrose asserts the authority of the church, refusing communion to the emperor Theodosius in Milan until he does penance for a massacre

The church of Santa Pudenziana in Rome begins the great tradition of Christian mosaics

Alaric and the Visigoths enter Rome and plunder the city - the first foreign intruders for eight centuries

Attila invades and ravages northern Italy, but turns back before reaching Rome - possibly influenced by the diplomacy of Leo I

Gaiseric and the Vandals enter Rome and sack the city, but their violence is perhaps restrained by Leo I

The mausoleum of Galla Placidia begins Ravenna's great tradition of Christian mosaic

The tribal leader and mercenary Odoacer becomes king of Italy - an event often taken as defining the end of the Roman empire in the west