The potato stands out as the key crop from the Americas that significantly spurred population growth across Europe. Introduced after Columbus's voyages in the late 15th century, it originated in the Andes and quickly proved superior in yield and nutrition compared to traditional staples like turnips or grains.

Historical Spread

Spanish explorers brought potatoes to Europe by the 1530s, with cultivation starting along Spain's coast and reaching Ireland via Sir Walter Raleigh. By the 18th century, potatoes had become a northern European staple—thriving in cooler climates unlike maize, which suited the warmer south—replacing root vegetables and enabling cereal-potato farming rotations. This shift fueled rapid population increases, as noted by historian William H. McNeill, by providing reliable calories that supported empires and armies from 1750 onward.

Caloric and Nutritional Impact

Potatoes offered four times the calories per acre of grains, grew underground to evade disasters, and provided vitamins that curbed diseases like scurvy. Post-1500, alongside maize and other New World crops, they helped Europe's population rise despite famines elsewhere, tripling in some regions like Tibet under similar adoption. However, the 1840s blight devastated reliance, hitting Ireland hardest and causing mass starvation and migration.

Why Not Other Crops?

While maize became vital in southern Europe (e.g., polenta) and cassava stayed tropical, potatoes' versatility and productivity made them the population driver in the north. Maize arrived earlier (1493) but lagged in cooler zones; beans integrated faster due to familiar European varieties. Recent forum discussions echo this, debating potatoes' role even in alternate histories.

TL;DR: Potatoes from the Americas revolutionized European agriculture, boosting populations through superior yields until blight risks emerged.

Information gathered from public forums or data available on the internet and portrayed here.