The potato (Solanum tuberosum) of the family Solanaceae (nightshade family) is one of the most widely used vegetables in Western temperate climates. The plant is probably native to the Andes, where it was cultivated by the Incas. In pre-Columbian times its culture spread widely among the Americas, where it was eaten as a staple food. Its history is difficult to trace, partly because the name potato was also used by early writers for the sweet potato (Ipomoea batatas) and for other unrelated plants.
Spanish explorers are believed to have brought it in the 16th century from Peru to Spain, whence it spread throughout Europe. It was brought to North America by European settlers probably c.1600; thus, like the closely related tomato, it is a reintroduced food plant in the New World.
The potato was first accepted as a large-scale crop in the British Isles. It became the major food in Ireland during the 18th century and is hence often called Irish potato to distinguish it from the sweet potato. Ireland was so dependent on the potato that the failure (resulting from blight) of the 1845–46 crop caused a famine resulting in widespread disease, death, and emigration.
The potato was also important to the course of history in the 20th century in Europe, especially in Germany, where it kept the country alive during two world wars.
With its high carbohydrate content, the potato is today a primary food of Western peoples. It grows best in a cool, moist climate. Germany, Russia, and Poland are the greatest potato-producing countries of Europe.
During the Alaskan Klondike gold rush, (1897-1898) potatoes were practically worth their weight in gold. Potatoes were so valued for their vitamin C content that miners traded gold for potatoes.
On the South Atlantic Island of Tristan de Cunha, potatoes were once used as the country's unofficial currency. Because of it's remoteness, food was most valuable.