Which 1492 event signaled a turning point for the Americas?

The arrival of Christopher Columbus in the Americas in 1492 marked a significant turning point, as it initiated widespread European exploration and colonization of the continent. This event led to profound changes in the indigenous populations, including the introduction of new diseases, cultures, and economies. The subsequent interactions between Europeans and Native Americans reshaped the social, political, and economic landscapes of the Americas, setting the stage for future conflicts and exchanges.