Bernhard Riemann.- Beginnings.- Doctoral Dissertation.- Privatdozent at Göttingen.- Riemann and Dirichlet.- Full Professor in Göttingen.- Last Years.- Posthumous Fate.- Topological Themes in Contemporary Physics.- Topological Structures.- The Connectivity of a Manifold and Quantization of Magnetic Flux.- Systems with Spontaneous Symmetry Breaking.- Topology and Liquid Crystals.- Theory of Gauge Fields.- Topological Particles.- Soliton Particles.- Knots, Links, and Physics.- What Next?.- A Brief Historical Survey.