After the War of the Frogs and the Mice Brouwer more or less retired from the scene. Freudenthal, Hopf's student, was appointed as his assistant in Amsterdam. Brouwer fought an investment scandal involving a health spa in Budapest, and founded a new mathematics journal, Compositio Mathematica. Heyting introduced his formal system for intuitionistic logic and arithmetic. The foundational atmosphere clearly was improving. The rise of the nazi regime is discussed, including an attempt of the new authorities to lure Brouwer to Göttingen; which predictably failed. At the end of the thirties Brouwer briefly returned to topology with a proof of the triangulation property for differentiable manifolds, only to find out that an American mathematician, Cairns, had already solved that case.