The document discusses how trade expanded during the Renaissance period due to the Crusades. The Crusades reestablished trade between Venice and other Italian cities with the East. They also exposed Europeans to new ideas from Muslim civilizations and brought back valuable goods from the East. This increased demand for trade. The Italian city-states like Venice, Genoa, and Florence became major trading hubs due to their geography, climate, independent governments, and social structures that supported business and trade. They competed for control of trade routes in the Mediterranean and Black Seas.