The complexities of Schleswig-Holstein run deep. Here’s Emil Nolde, an artist born south of the German-Danish border and steeped in the marshy mysteries and primal romanticism of that landscape. In 1920, he sees his region, and himself, become Danish following a post-Versailles plebiscite. An already well-established German nationalist bent — pronounced despite, or perhaps because of, his shifting national identity and shaky grasp of the German language — is inflamed.