Abstract: Dirichlet was a famous German mathematician and mathematical educator who devoted his whole life to promoting German mathematics. He set up his ambition at a young age and persisted in it tenaciously. With the help of Humboldt, Gauss and many other distinguished figures, he gradually grew into a mathematical giant and made original contributions in many mathematical fields, especially in number theory. He actively participated in higher mathematics education in Germany, created curriculum models, significantly improved German mathematics teaching level, cultivated a large number of mathematical talents including Dedekind and Riemann, and ultimately moved the center of mathematical world from France to Germany. As an important figure in promoting German mathematics, his success is still of enlightening significance today.

Key Words: Dirichlet; Number theory; Mathematics education; Humboldt; Gauss