The story of how the French came to love potatoes is a dramatic one. The potato went from disgusting pig food to leprosy-causing toxin to a "food of the people" during the French Revolution. It was described as a ray of hope for common people by the king of France right before he was executed by said people during the revolution for being an enemy of the people.
Potatoes are a standard presence in the modern world. Aloo-this, sauteed-that... we love potatoes and have invented a thousand recipes to relish this amazing starchy vegetable we cannot get enough of. French fries are among the most popular guilty pleasures for most 21st-century humans. So, it comes as a bit of a surprise to learn that until three centuries ago, the people of France despised potatoes. Potatoes were illegal in 18th-century France, and it took a war with Prussia for the French to realize that today’s much-loved vegetable does not cause diseases and is not toxic.
The upper echelon of 18th-century French society expressed their contempt for potatoes in the books they wrote, even describing it as a pasty flavor besmirched by "a natural insipidity" that lent it an "unwholesome quality." Pierre Jean-Baptiste Legrand d'Aussy, a historian of that era, wrote, "...send it to the common people, whose coarser tastes and...robust stomachs are satisfied by everything which is capable of appeasing hunger." I'm guessing that rude historian would find it difficult to appreciate the joys of modern French fries with a good serving of ketchup.
Potatoes made their way to Europe from (where else but) South America in the 16th century, thanks to (who else but) the Spanish. By the 18th century, this vegetable had grown in popularity and was being cultivated all over Europe. Spain, Ireland, and England took a liking to the potato and added it to their regular diets fairly quickly. Most other European societies grew it as food for domesticated pigs. Sweden used it as an ingredient in making cheap Swedish brandy. It was also largely seen as cheap food for the impoverished, who had it when the kitchen ran empty. Many farmers of the time believed that potatoes were poisonous to the human body. That unsubstantiated fear spread far and wide, so much so that the French parliament in 1748 made it illegal to cultivate potatoes because they believed that they caused leprosy. Pig food, leprosy, poverty rations—you can see why Europeans didn’t like potatoes all that much.
In the eastern parts of Europe, in Prussia, the rulers had tried to get the people to eat more potatoes as a solution to famine. But the overall population went "meh" so in 1756, Frederick the Great, then king of Prussia, issued the Potato Decree (Kartofellbefehl). The decree aimed "to make the rulers and subjects understand the benefits of planting this earth plant and to advise them that they should do so this morning -Year plant the potatoes as a very nutritious food." Legend has it that Frederick II would even stop during his travels through his lands to check the execution of his order! He ordered those potatoes to be grown "wherever there is an empty spot to be found." He may have been didactic, but he wasn’t wrong, objectively speaking. When the Seven Years War broke out in 1756, and went on for, well, seven years until 1763, Prussia was the only region to not suffer from mass starvations.
This is where the story gets interesting for the French. Antoine-Augustin Parmentier was a pharmacist working for the French army during the Seven Years War. France was fighting against Britain and Prussia in that war, and Parmentier was captured by Prussian troops. He was imprisoned for three years. We know what the King of Prussia thought of potatoes. So, Parmentier had to eat a lot of potatoes over the course of his time in jail. After eating potatoes for a long time and not developing leprosy, the pharmacist had a lightbulb moment: maybe potatoes are not dangerous. Perhaps the doctors in France made a mistake conflating potatoes with disease and, like the Prussians, the French could end famines by using potatoes.
In 1763, he is released from prison and makes his way back to Paris. Potatoes were still illegal and were targeted by a popular French economist, Francois Quesnay. The economist claimed that potato farming barely kept farmers alive while ruining them physically and causing the death of many of them in childhood. Even the French clergy had a negative opinion of potatoes, claiming that God did not approve of them as they find no mention in the Bible.
Some years later, in 1770, France was faced with another failed harvest. People were open to new ideas, and the potato talk must have gotten around the country because attitudes began to change. Parmentier wrote an essay on the virtues of the potato and won a contest where he pitched it as a reliable substitute for "ordinary food" during "times of necessity." His word caught on, and in 1772, the Paris Faculty of Medicine overcame its disgust for potatoes as pig feed and declared the vegetable fit for human consumption. Potatoes were finally legal in France, but they were still pretty unpopular.
Parmentier went on a charm offensive. He hosted dinner parties for prominent members of society, including an American named Benjamin Franklin. The dinners had multiple courses that featured potatoes prominently. In 1785, he presented the French king and queen a bouquet of purple potato flowers. The king and queen grew fond of them and were seen wearing them on more than one occasion. Then, King Louis XVI gifted him land outside Paris where he could grow potatoes. The king told Parmentier, "France will thank you one day for you have found bread for the poor."
While the king and queen were okay with potatoes, the people of France were still skeptical. So, he came up with a clever ploy. He paid soldiers to guard his potato fields during the day. But only during the day. He wanted to project that the fields had something very valuable worth guarding by soldiers all day. He had them look the other way at night if someone was curious or stole his valuable produce. He even instructed them to take any bribes offered by people who wanted to see what was so valuable. This strategy worked because Parmentier intended for people to steal potatoes at night. Place guards around something, make it seem precious, and the people will want the forbidden thing.
Parmentier continued to campaign for the potato and also had a book printed with the help of the king. That was just a few days before the French Revolution broke out. However, the potato soon became a favorite with common folk and was known as the food of the people, and the rest is history. Parmentier was praised by one contemporary as the "Virgil, Cicero, and Homer of the potato." To this day, his tomb in Paris' famous Pere-Lachaise Cemetery will have visitors place a tuber or two in respect for his work. If not for him, France couldn’t lay claim to being the originator of French Fries (which are probably Belgian), but that’s a story for another time.