Gauge theories, Simple Groups and Integrable Systems
In this review we discuss interrelations between classical Hitchin integrable systems, monodromy preserving equations and topological field theories coming from N=4 supersymmetric Yang-Mills theories developed by Gukov, Kapustin and Witten. In particular, we define systems related to bundles with nontrivial characteristic classes and discuss relations of the characteristic classes with monopole configurations in the Yang-Mills theory.