How did a bitter Aztec drink become Europe's sweet craze?

Chocolate crossed the Atlantic almost by accident, and it needed a makeover to survive the trip. In 1502, on Columbus's fourth voyage, his crew met a Maya trading canoe and noticed that its crew valued cocoa beans, but they did not know what the beans were, nor that they could make a drink. Hernán Cortés may have been the first European to encounter chocolate itself, in the court of Moctezuma II in 1520.

At first the Spaniards living in the Americas did not like it. Chocolate was an acquired taste, widely disliked until the 1590s, and the foam was found particularly objectionable. So they changed it. It was often sweetened, flavoured with familiar spices and served warm, and the foam was made just by beating it with a molinillo, a wooden whisk.

The drink reached Spain in documented form in 1544, when Maya nobles brought to Spain by Dominican friars presented it to the court. Spain saw it mainly as medicine. From Spain it spread to Portugal, to Italy in the 17th century, and onward, with religious orders playing a significant role. By the 17th century it was very popular among Europe's elite, and expensive because of high transport costs and import duties.

Then came a surprising argument. Was chocolate a food or just a drink? It mattered, because food would break a religious fast. The dispute ran from the late 16th to the early 18th century, and several popes said it did not break the fast. In England, chocolate arrived around 1657, at about the same time as tea and coffee, and by the end of the century it was compulsory in British Navy rations.