Chocolate comes from cocoa beans, which grew on trees in Central America starting probably about 100 million years ago; cocoa trees may have gotten their start on the lower slopes of the Andes Mountains. Cocoa trees can only live in hot, rainy places.The trees bear large orange fruit, about the size of small pumpkins. You pick the fruit, and many small beans are inside, like peas inside a peapod. The raw beans are really good for you, full of vitamin C and magnesium, but they're bitter. They also have a fair amount of caffeine in them, like coffee or tea, and can help you work harder than you could without cocoa. People probably ate cocoa beans as soon as they got to Central America, maybe about 15,000 BC.
By around 2000 BC, pre-Olmec people in Central America (modern Mexico) were grinding up the beans and making them into a hot or cold spicy chocolate drink with vanilla or chili peppers. All the people of Central America - the Olmec, the Zapotec, the Moche, the Maya, and the Aztecs - liked chocolate.
By the 600s AD, Maya farmers were growing cocoa trees instead of picking wild cocoa. The Aztec government made people pay a lot of their taxes in cocoa beans, because they were expensive and you could store them for a long time. Once the government made people use cocoa beans as money, most people couldn't afford to actually eat them anymore, and only rich people drank the chocolate drinks.
In the 1500s, Spanish conquistadors such as Hernán Cortés who sought gold and silver in Mexico returned instead with chocolate. Although the Spanish sweetened the bitter drink with cane sugar and cinnamon, one thing remained unchanged: chocolate was still a delectable symbol of luxury, wealth and power. Chocolate was sipped by royal lips, and only Spanish elites could afford the expensive import.
Spain managed to keep chocolate a savory secret for nearly a century, but when the daughter of Spanish King Philip III wed French King Louis XIII in 1615, she brought her love of chocolate with her to France. The popularity of chocolate quickly spread to other European courts, and aristocrats consumed it as a magic elixir with salubrious benefits. To slake their growing thirst for chocolate, European powers established colonial plantations in equatorial regions around the world to grow cacao and sugar. When diseases brought by the European explorers depleted the native Mesoamerican labor pool, African slaves were imported to work on the plantations and maintain the production of chocolate.
Chocolate remained an aristocratic nectar until Dutch chemist Coenraad Johannes van Houten in 1828 invented the cocoa press, which revolutionized chocolate-making. The cocoa press could squeeze the fatty cocoa butter from roasted cacao beans, leaving behind a dry cake that could be pulverized into a fine powder that could be mixed with liquids and other ingredients, poured into molds and solidified into edible, easily digestible chocolate. The innovation by van Houten ushered in the modern era of chocolate by enabling it to be used as a confectionary ingredient, and the resulting drop in production costs made chocolate affordable to the masses.
In 1847, British chocolate company J.S. Fry & Sons created the first solid edible chocolate bar from cocoa butter, cocoa powder and sugar. Rodolphe Lindt’s 1879 invention of the conching machine, which produced chocolate with a velvety texture and superior taste, and other advances allowed for the mass production of smooth, creamy milk chocolate on factory assembly lines. You don’t need to have a sweet tooth to recognize the familiar names of the family-owned companies such as Cadbury, Mars and Hershey that ushered in a chocolate boom in the late 1800s and early 1900s that has yet to abate.
For more information visit http://www.history.com/news/hungry-history/the-sweet-history-of-chocolate
https://en.wikipedia.org/wiki/Chocolate