freshly baked, quality croissant is a marvel. It is part architecture and part alchemy; a miracle rendered in butter, flour, and sugar that is simultaneously crisp and pillow-tender, ethereally buttery yet light enough to eat at the start of the day.

The modern croissant is made up of water, milk, flour, yeast, sugar, and fat—usually butter, sometimes margarine. The crescent-shaped pastries are fashioned from laminated dough, usually with a ratio of three parts butter to ten parts flour. Pastry chef François Payard (a third-generation baker and the chef of FP Patisserie in New York) says that when the pastries bake the butter makes little pockets of steam in the dough, which creates the layers that give a croissant its unmistakable flakiness. You know you have a perfect croissant when you cut it in half and see "alveoli"—Payard adopts the word for the sacs in our lungs—in the middle.

But how did buttery little crescent moons with lung sacs in them make their way to our table? By following the history of those ingredients and the people who put them together, the story of the croissant tells the story of Europe as a whole. Rising and falling empires, wars, and marriages all contributed to the croissant as we know it today.