Snippet from Wikipedia: Roman Empire

The Roman Empire was the state ruled by the Romans following Octavian's assumption of sole rule under the Principate in 27 BC, the post-Republican state of ancient Rome. It included territories in Europe, North Africa, and Western Asia and was ruled by emperors. The fall of the Western Roman Empire in 476 AD conventionally marks the end of classical antiquity and the beginning of the Middle Ages.

By 100 BC, Rome had expanded its rule to most of the Mediterranean and beyond. However, it was severely destabilized by civil wars and political conflicts, which culminated in the victory of Octavian over Mark Antony and Cleopatra at the Battle of Actium in 31 BC, and the subsequent conquest of the Ptolemaic Kingdom in Egypt. In 27 BC, the Roman Senate granted Octavian overarching power (imperium) and the new title of Augustus, marking his accession as the first Roman emperor of a monarchy with Rome as its sole capital. The vast Roman territories were organized into senatorial provinces, governed by proconsuls who were appointed by lot annually, and imperial provinces, which belonged to the emperor but were governed by legates.

The first two centuries of the Empire saw a period of unprecedented stability and prosperity known as the Pax Romana (lit. 'Roman Peace'). Rome reached its greatest territorial extent under Trajan (r. 98–117 AD); a period of increasing trouble and decline began under Commodus (180–192). In the 3rd century, the Empire underwent a crisis that threatened its existence, as the Gallic and Palmyrene Empires broke away from the Roman state, and a series of short-lived emperors led the Empire.

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