It occurred to me that global trade is much older than we usually think. We emerged from the Stone Age when people learned to make tools out of bronze. But bronze, while easy to make, requires tin, which is a rare element. In the ancient Mediterranean and Near East, there were only a few skimpy sources of tin. The most plentiful supplier of tin was Cornwall, on the island of Great Britain. Most of the people making bronze in Greece or the Levant didn't know where the tin came from. If you asked them what people were like in the legendary northern isles, they would have supposed them to be savages. But tin was traded from Britain to what was later Gaul and Hispania, and traded on from Massilia and Carthage to destinations all over. Without British tin, the Bronze Age could not have brought its advances to Greece, to Egypt, to Assyria, to Rome.
In terms of luxury goods, you could make the same case for amber. Amber was traded from the Baltic, where it was produced, to the Mediterranean and Near East, passing through many intermediaries to reach markets in the classical world.
Goods passed the other way, too. Archaeologists have found many artifacts from the Mediterranean in deposits from the Bronze Age in Britain. Even before coinage was invented, there was a single economy that spanned societies where people could barely imagine life at the other end of the trade network.