Rome was a military powerhouse. Certainly, the old empire was an economic power in the world during the height of its prosperity, but historians will never forget that the ever-widening gap between rich and poor eventually (and inevitably) helped to bring it to its knees. Especially when compared to Rome’s age-old enemy, Carthage, which acquired power and influence through business and economy.
Byzantine was different.
The eastern empire was a force with which to be reckoned both militarily and economically, which helped set it apart from those earlier civilizations. Constantinople was hailed as the “hub” for much of the trade done throughout the empire for centuries. Those networks extended through much of the known world — almost all of Eurasia was included, and even some parts of North Africa.
The economy was so advanced that basic forms of credit were used for some purchases. Banking practices seem to be much more advanced than scholars once believed. The monetary system, which was based on coinage, lasted for more than a millennia. The emperor was responsible for supervising the minting of these coins, but the government in general controlled the money.
Trade was the most important factor in growing the empire’s economy. It wasn’t unheard of for Byzantine products to make their way to far-away locations like Norway, Livonia, Bulgaria, etc. Grain was an important commodity because an insane amount was needed to feed the people who lived and thrived within the empire’s borders. Silk was equally important because it helped play a role in diplomatic ventures.
Silk would routinely be purchased from China before being distributed all over the world. Silk comes from silkworms, though — and those were inevitably smuggled into the borders of the Byzantine Empire.
At that point, there was little reason to purchase silk from China. Because the trading of silk no longer required the use of those long-distance trade routes to China, it was easier for the empire to control and monopolize. Afterward, it essentially became a state-owned product. The empire only sold it to those it wanted.
Oil and wine were popular commodities as well. Oil was used both for cooking and personal grooming. And of course wine was a beverage of choice for many citizens of the empire. Other products included fish, meat, salt, vegetables, wax, and timber.
Wealthier residents might be able to afford the aforementioned silk, or commodities such as perfume and spices. Slaves weren’t as important as they were in Ancient Rome, but they were still important to Byzantine’s economy.
The wealth of the empire slowly deteriorated over time — mostly due to the many wars in the east that slowly eroded its fortunes.