Euler and the German Princess

In 1760, Leonhard Euler began to write beautiful Letters to a German Princess on Diverse Subjects of Physics and Philosophy. Much has been written about Euler and his work, but we wonder, who was the princess? How did she become involved with the greatest mathematician of her time? The princess was a fifteen year old named Friederike Charlotte von Brandenburg-Schwedt. In this article we explore her story and the nature of the letters.