Bernhard Riemann was a German mathematician born in 1826 who died in 1866. He studied at the Universities of Gottingen and Berlin where he learned from notable mathematicians like Dirichlet and Jacobi. In 1854, he was appointed as an unpaid lecturer at Gottingen and later became a full professor there in 1859 replacing Dirichlet after his death. Riemann made significant contributions to higher mathematics through his work in complex analysis and the geometry of multiple dimensions, developing concepts now known as Riemann surfaces and Riemannian geometry.