Geometry and quasi-classical quantization of magnetic monopoles

We present the basic physical and mathematical ideas (P. Curie, Darboux, Poincare, Dirac) that led to the concept of magnetic charge, the general construction of magnetic Laplacians for magnetic monopoles on Riemannian manifolds, and the results of Yu.A. Kordyukov and the author on the quasi-classical approximation for the eigensections of these operators.