Whole grain oats have been consumed by many people since 7,000 B.C. and were among the first cereal grains to be cultivated. Oat cultivation found its way to Britain during Roman times where the climate, especially in Scotland is well suited to growing the grain. Oats can thrive in a moist, cool climate, like that of Scotland, where wheat and barley cannot. Besides used as a cereal grain for humans and livestock, oats are also occasionally used in several different drinks. In Britain, they are sometimes used for brewing beer - oatmeal stout. A cold, sweet drink called avena made of ground oats and milk is a popular refreshment throughout Latin America. Oatmeal caudle, made of ale and oatmeal with spices, was a traditional British drink and a favourite of Oliver Cromwell. In Scottish English, oats may be referred to as "corn," a reference often used for the major staple grain of the local area, while in the US, "corn" originates from "Indian corn" and refers to what others call "maize" or "sweetcorn."