I think that turnips were kind of more filling the place that potatoes did.

Then the Columbian exchange happened and suddenly Europe had potatoes and turnips got kind of displaced.

https://www.washingtonpost.com/history/2018/10/08/christopher-columbus-potato-that-changed-world/

Before Columbus landed on Hispaniola, the European diet was a bland affair. In many northern climes, crops were largely limited to turnips, wheat, buckwheat and barley. Even so, when potatoes began arriving from America, it took a while for locals to realize that the strange lumps were, comparatively speaking, little nutritional grenades loaded with complex carbohydrates, amino acids and vitamins.

“When [Sir Walter] Raleigh brought potatoes to the Elizabethan court, they tried to smoke the leaves,” Qian said.

Eventually, starting with a group of monks on Spain’s Canary Islands in the 1600s, Europeans figured out how to cultivate potatoes, which form a nutritionally complete — albeit monotonous — diet when combined with milk to provide vitamins A and D. The effects were dramatic, boosting populations in Ireland, Scandinavia, Ukraine and other cold-weather regions by up to 30 percent, according to Qian’s research. The need to hunt declined and, as more land became productive, so did conflicts over land.

Frederick the Great ordered Prussian farmers to grow them, and the potato moved to the center of European cultures from Gibraltar to Kiev. "Let the sky rain potatoes,” Shakespeare wrote in "The Merry Wives of Windsor.” Their portability made them ideal to transport into the growing cities, feeding the swelling population that would be needed for a factory labor force.

“It’s hard to imagine a food having a greater impact than the potato,” Qian said.