Rome's empire expanded greatly over the first few centuries AD. Under emperors like Augustus, Rome conquered territories across Europe and Northern Africa, including Gaul, Britain, Asia Minor, Mesopotamia. This spread Roman control over the Mediterranean world and beyond. The empire promoted trade as Romans needed resources from the provinces to supply Rome. Traders brought goods across the empire in exchange for Roman coins and currency. The first 200 years of the empire saw the Pax Romana, a period of general peace and stability that allowed Rome to grow wealthy and its population to increase as trade flourished.