Aim: What were the major similarities and differences between the Spanish and Portuguese Empires? Imperialism- a policy of extending a country's power and influence through diplomacy or military force. Old Imperialism- refers to European imperialist activity before the advancements of the Industrial Revolution that enabled the complete subjugation of the globe. The “Old” era is characterized by trading posts and coastal dominance, piracy of sea-trade, the Atlantic Slave Trade, and Columbian Exchange. “Old World” populations couldn’t be conquered at this time (Except for New World civilizations).