A major factor in bringing about the Pax Romana was trade. Egypt was the richest province in the Empire, and the money it brought in helped Augustus to build up vast numbers of clients.
The Pax Romana was the only time in history when the whole Mediterranean and the lands around it were at peace under a united government. Because everyone in the Empire lived under Roman law, and most people could speak Latin, trade flourished and the people prospered. The empire was connected by its vast network of roads, which were built for military purposes, but which helped communications of all kinds. The navy suppressed piracy, and the seaways provided a faster, cheaper way of transporting goods. All this helped to bring the peoples and provinces together.
The currency was the same throughout the Empire. At that time, of course, there were no newspapers or television, and coins provided a very concise form of mass communication. Each coin had space for a little piece of propaganda, showing an image of the emperors face together with a slogan. Claudius celebrated the conquest of Britain by minting coins with the legend De Britann(is). Another slogan, Concordia Militum, meant goodwill among soldiers - probably more wishful thinking than fact.
A small bronze quadrans was enough to get into the public baths. Four quadrans made an as, another small bronze coin. Two asses made a dupondius; four asses made a sestertius; sixteen asses made a denarius, a days wages for a craftsman. A hundred asses made an aureus. So many coins remain that they are quite cheap to buy. Historians find them valuable not only because of their inscriptions and pictures, but also because they can help to date a site in an excavation.
The provinces had to provide tribute and taxes, which they paid in goods more often than in money. The goods reached Rome through the port of Ostia, 15 miles away at the mouth of the Tiber, and also came through Puteoli, near Naples. The most important commodity was grain. Every year over 400,000 tons of grain came from North Africa, Egypt and Sicily to feed the people of Rome. Without it, the people would have starved.
Every Roman who was not a patrician was a plebeian. The nobles despised trade as degrading and vulgar. Rome was filled with traders of all kinds: goldsmiths, coppers, girdlemakers, fruit-sellers, fishmongers, butchers, bath attendants, polishers, porters, shopkeepers, labourers, fortune-tellers. Among the poorer plebeians, women worked as the equals of men: we know that some of them were midwives, dressmakers, mime artists... A woman called Eumachia owned her own brickyard in Pompeii. Educated women, after the time of Augustus, might even become teachers or doctors. Most plebeians were poor, but some, such as bankers, factory owners and merchants, were very rich.
A stone relief survives, depicting a butcher chopping meat with a cleaver. Joints of meat are hanging from a rail. A woman, probably a customer waiting for her order, is sitting with a shopping list in her lap.
Weights were checked by officials to make sure that traders did not cheat their customers. Roman traders used two types of scales: the balance type and the steelyard type. The simple balance scales were usually made out of bronze, as were the steelyards. The steelyard was hung up by a hook. The item to be weighed was placed in a pan attached to a lower hook on the left, or the pan could be replaced with a bag. A weight was moved to the right until the arm balanced horizontally. A scale inscribed along the arm would mark the weight of the goods.
Most traders operated either from residential shops or from rented space in the forum or market. Travelling merchants or country dwellers would use the porticoes or open spaces in the public markets. Shops might cluster together in rows and form whole streets in the centre of town. At Cirencester, excavations show a row of shops that were originally built in timber, but gradually were rebuilt in stone as the shopkeepers could afford it. Timber and stone shops existed side by side until the fourth century, by which time all were made of stone. This suggests that each shop was under separate ownership, though sometimes two shops were joined by communicating doors, suggesting expansion. A shopkeeper might be the owner, a freedman-tenant, or a slave-manager. In Norton, Yorkshire, an inscription refers to a goldsmiths shop which was clearly run by a slave.
Rome depended on the provinces to provide luxuries. Spain provided wine, olive oil, honey, salt fish, wax, pitch, cochineal (a red dye made from crushed beetles), black wool and fine cloth. Wine also came from France, and more cloth was imported from Syria, which also provided glassware; silks came from the Far East and robes came from Babylon. Shoes were imported from Greece, incense from Arabia. Marble arrived from Africa and Asia, gems were brought from India, amber from the Baltic. Italy exported wine to Gaul and Britain. Aristides described Rome as a common market for the world.
Unfortunately, not all of this was good news for the provinces. Governors and tax collectors received no wages from the state; they squeezed out extra money from the inhabitants on top of the taxes owed, depending on that for their living. It seems that the governors were not particularly merciful, since their job was considered a way to get rich quickly. The trade in animals for the games resulted in the extinction of lions and elephants in North Africa and the Middle East. Unrestrained land-clearing in North Africa reduced rainfall and made the soil barren, turning vast areas into desert. As early as AD 100 Tacitus quoted Calgacus, a British chieftain, as saying: The Romans have exhausted the land by their plunder. Robbery, butchery... they create a wasteland, and call it peace. And Juvenal advised new governors to spare a thought for the poor locals - youll find theyve already been bled dry. Some historians believe that this exploitation caused the provincial population to fall, which in turn contributed to the decline of the Empire.