Who invented chocolate?
Nobody alone. People in Mesoamerica drank cacao for thousands of years, Europeans sweetened it, Joseph Fry made the first modern bar in 1847, and Daniel Peter in Switzerland made milk chocolate in the 1870s.
ChocolateA 100 g bar535kcal
A drink in Mesoamerica
Chocolate started as a drink, not a bar. Smithsonian Magazine says the earliest evidence of people consuming it goes back three or even four thousand years, to cultures of Mesoamerica such as the Olmec. Pottery from Honduras from around 1400 BC holds cacao residue, which suggests the sweet pulp of the fruit was fermented into alcohol. Britannica says the Maya, Toltec and Aztec peoples all grew cacao and made a drink from it, and the Maya buried important people with bowls of chocolate.
Beans worth a turkey
Cacao mattered so much that the beans were money. Smithsonian Magazine says one bean could buy a tamale and 100 beans could buy a good turkey hen. The Aztec drink was bitter and often spiced, and both the Aztecs and the Maya thought the beans had magical or even divine powers. There is a famous story that the Aztec ruler Montezuma welcomed Hernán Cortés with chocolate because he took him for a god. Smithsonian treats that one as a legend, so take it as such.
Europe adds sugar
The Spanish were not impressed at first. Smithsonian quotes the drink being called a bitter drink for pigs, until it was sweetened with honey or cane sugar. Britannica says Columbus brought beans to Spain after 1502, and the first recorded shipment came from Veracruz in Mexico in 1585. Served hot and sweet, it became fashionable at the Spanish court. By 1657 you could buy chocolate in London, though only the rich could afford to drink it.
From a cup to a bar
Then came the machines. In 1828 the Dutch chemist C. J. van Houten patented a way to press most of the fat, the cocoa butter, out of roasted beans, which gave us cocoa powder. In 1847 the English firm Fry and Sons mixed cocoa butter back in with chocolate liquor and sugar and made the first solid eating chocolate. In 1819 François-Louis Cailler had already opened what Swissinfo calls the world's first mechanised chocolate factory, near Vevey in Switzerland.
The Swiss add milk
Milk chocolate came from Vevey too. Daniel Peter started his chocolate business there in 1867 and worked with condensed milk from his neighbour Henri Nestlé. Swissinfo dates his milk chocolate to 1875 and calls it an immediate hit across Europe. Britannica gives 1876 and says he used dried milk, so the sources disagree on the year and the milk. In 1879 Rudolf Lindt in Bern built the conche, which made chocolate smooth. The bar you break into squares today is the sum of all of them.