It lasted for more than a thousand years. Its Great Palace was the seat of imperial and religious government for as long. It claimed to encompass the Roman Empire, and often did. It was the largest and greatest court in Christendom. In its Chrysotriklinos, its Golden Hall, hydraulic engines powered fountains, large organs, golden birds that sang in jewel-drenched trees, and golden lions that roared. Ambassadors bowed to its emperor as his throne magically rose to the ceiling. Gold mosaics dazzled visitors to its court and cathedral.
It was Byzantium.
I’m reading Judith Herrin’s history of that empire. She is a good historian but perhaps not much interested in economics. In her book, Byzantium: The Surprising Life of a Medieval Empire, an essential fact of Byzantine economy gets a fleeting mention as a caption to an illustration: “Byzantium preserved a gold coinage of reliable fineness over 700 years.”
Many empires have been laid low by the degradation of their currency. I think ours is next. No historian will ever say that the US dollar preserved reliable fineness for even a tenth of 700 years.