We present a project in which we investigate the chances of sentiment analysis in the context of German historic plays, more concretely eleven plays by G.E. Lessing. We evaluated several lexicon-based sentiment analysis techniques against a gold standard of 200 speeches that were manually annotated with sentiment information in an annotation study. The combination of methods with the best performance was used to create a web-based tool. The tool allows users to explore sentiment progressions and distributions on structural levels (acts, scenes, speeches) as well as for speakers and speaker relations.