In order to control their large empire, the Romans developed important ideas about law and government. They developed the best army in the world at that time, and ruled by force. They had fine engineering, and built roads, cities, and outstanding buildings. The Empire was divided into provinces, each with a governor plus civil and military support. Letters, both official and private, would constantly go to and from Rome.
Trade was most important for Rome, a city of more than a million people, by far the largest city in the world. They needed, and got, wheat from Egypt, tin from Britannia, grapes from Gaul, and so on. In return, the Romans built provincial capitals into fine cities, protected them from raids by barbarians, and provided education and career opportunities for young people in the provinces, such as jobs in the Roman Army.

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