Answer:
The Middle Ages at first was a period in which the opposite occurred: half of Europe went from being united under the Roman Empire, to becoming a plethora of small states, often at war with each other.
As the Middle Ages progressed, international trade and globalization began to flourish again. One empire that contributed to this was the Byzantine Empire. Another state (not necessarily an empire) was the Venice Republic, which had trade routes all over the Mediterranean, but also as far as the Middle East, India, and China, thanks to the Silk Road.
In modern times, globalization has taken way more force than in the Middle Ages. All countries of the world engage in international trade (even very closed-off countries like Cuba or North Korea), and this boosts globalization even more in a positive feedback loop that is ever accelerating. Globalization determines the economic decisions of individuals, firms, and governments, and its effects are difficult to predict, but tend to be positive, at least according to most economists.
