In 1854, Riemann gave his first lectures, which established the field of Riemannian geometry, and laid down the foundation for Einstein's General theory of Relativity.
In 1857, at the University of Göttingen, endeavors were made to sponsor Riemann to an extraordinary professor rank. Although this didn’t materialize, this attempt opened doors of regular salary for Riemann.
In 1859, at Göttingen, Riemann was promoted as the head of the mathematics department and, the same year, he also got elected as a corresponding member of the Berlin Academy of Sciences. As a freshly elected member, Riemann presented a report on ‘The number of primes less than a given magnitude’, which proved to be of fundamental importance in number theory. Riemann also pioneered in the use of dimensions higher than only three or four, in order to explain physical reality.
In 1866, Riemann was forced to flee Göttingen when the armies of Prussia and Hanover collided there during the Austro-Prussian War.