The "Columbian Exchange"—a phrase coined by historian Alfred Crosby—describes the interchange of plants, animals, and diseases between the Old World and the Americas following Columbus's arrival in the Caribbean in 1492. For reasons beyond human control, rooted deep in the divergent evolutionary histories of the continents, the Columbian Exchange massively benefited the people of Europe and its colonies while bringing catastrophe to Native Americans.
The Columbian Exchange: It's a relatively obscure concept, developed by a relatively obscure historian. Most people have never even heard of it. Its definition—the transmission of non-native plants, animals, and diseases from Europe to the Americas, and vice versa, after 1492—doesn't sound very sexy. And yet the Columbian Exchange just may be the single most important event in the modern history of the world.
The Columbian Exchange explains why Indian nations collapsed and European colonies thrived after Columbus's arrival in the New World in 1492.
The Columbian Exchange explains why European nations quickly became the wealthiest and most powerful in the world.
The Columbian Exchange explains why Africans were sold into slavery on the far side of the ocean to toil in fields of tobacco, sugar, and cotton.
The Columbian Exchange even explains why pasta marinara has tomato sauce.
If you don't understand the Columbian Exchange, you cannot truly understand the forces that shape the world we live in today. You cannot understand why you speak the language you speak, why you live in the nation you live in, or even why you eat the food you eat.
If you don't understand the Columbian Exchange, much of what you think you know about the history of the Americas may be wrong. Spanish soldiers did less to defeat the Incas and Aztecs than smallpox did. Divine Providence did less to bless the Puritan settlers of the Mayflower with good health and fortune than the Pilgrims' own immune systems did.
In the Columbian Exchange, ecology became destiny. Powerful environmental forces, understood by no one alive at the time and by very few people even today, determined who would thrive and who would die. And that may be the most shocking truth revealed to those who take the time to understand the Columbian Exchange: we, as humans, cannot always control our own destinies. The most important historical actors in this story are not Christopher Columbus or Moctezuma or Hernán Cortés. They are the smallpox virus, the pig, the potato, and the kernel of corn.