Imperial Rome describes the period of the Roman Empire from 27 B.C.E. to C.E. 476. At its height in C.E. 117, Rome controlled all the land from Western Europe to the Middle East.

The first Roman emperor was Augustus Caesar, who came to power after the assassination of Julius Caesar, his great-uncle. Augustus helped restore the city of Rome and secured its frontiers during his reign. He also reformed laws and initiated large building projects within the imperial capital. After his death, his successors continued pushing Rome’s frontiers further. However, a period of unrest followed, which caused the empire’s development to be temporarily stalled.

By C.E. 96 the Nervan-Antonin Dynasty began and resumed the empire’s development. Among these leaders were Nerva, Trajan, Hadrian, Antoninus Pius, and Marcus Aurelius. Collectively, they are known as the Five Good Emperors and they expanded Rome’s frontier to the height of its expansion, controlling territory from Britain all the way to parts of Mesopotamia.

However, the size of the empire made it difficult to control from Rome alone. The emperor Diocletian decided to divide it into western and eastern halves in C.E. 285 to make managing the empire easier. Competition between the leaders of the halves emerged and resulted in civil war, which ultimately led the general Constantine to unify the empire under his own rule. He decided to move the imperial capital from Rome to the site of the ancient city of Byzantium, renaming the city Constantinople, and developing it further in the Roman style.

Once Constantine moved the capital, Rome transitioned to a period of decline. War, a weakened treasury, and deterioration of infrastructure led to the loss of territory in the western half of the empire. The Western Empire finally collapsed in C.E. 476 while the Eastern Empire continued on as the Byzantine Empire until the city fell in C.E. 1453.