Bread was always the "staff of life" in Europe, from the time of the ancient Romans and their "bread and circuses" to keep the masses happy (the modern equivalent is "fast food and television"). But we Americans, eating our daily potatoes, rice and pasta, may not realize how the "daily bread" of the Our Father prayer may have been all our ancestors had to eat for months at a time. The English language has plenty of traces of this, from the word lord which once meant the man who gave you bread, to the expression "breadwinner" to the old slang "bread" for money.
One of the causes of the French revolution was that a series of crises (one of them was France's expensive support for the American revolution) had led to a rise in the price of bread, making it so expensive that people began to starve. The wheat harvest of 1788 was disastrous. On October 5, 1789, thousands of poor women marched from Paris to Versailles, crying out "Bread!" and chanting, "We will lack bread no more, we will bring back the baker, the baker's wife, and the baker's boy" (Nous ne manquerons plus de pain, nous ramenons le boulanger, la boulangère, et le petit mitron). They forced the king, Marie Antoinette and their children to come to Paris, along with a convoy of fifty or so carts of grain and flour. The king, his wife and their son died in their Paris captivity, and only their daughter lived. (She was freed at age 17, never having been told what the fate of her family was, and left a sad little note scribbled on the wall of the tower room where she had been caged for seven years: "Marie-Thérèse-Charlotte is the most unhappy person in the world.")
After the revolution, the potato began to make inroads in France. It was easier and cheaper to cultivate and wholesome to eat. But bread is still something that most traditional French people still eat every day, often with every meal. To this day, the price of bread is controlled in France, and the préfecture of each département has to approve the dates when bakeries can close for their annual vacation, so that people don't have to go without their baguettes.