With a POD as far back as you want without ASB, is it possible to have any other body of water have a history similar to that of the Mediterranean of being a unified continium of cultures, empires, etc. One may see similarities in a later date of the Indian Ocean, during Arab domination before Portugal arrived. And the South Pacific with the Polynesian dispersal, but again their kingdoms came quite late and were just above clans, nothing except in Indonesia of true empires. But several bodies of water surely had the geography that lends to such unification of culture but didnt.
What made the Mediterranean unique? Geography, simply nothing like it on earth honestly?
But why didn't the Persian Gulf, Caspian Sea, the Great Lakes in North America, or the Gulf of Mexico develop in parallel?