From 1844 to 1851, he held the chair of history at Humboldt University in Berlin, and in the meantime, served as an adviser to Frederick William IV of Prussia. In 1851 he returned to Basel, where he edited the Protestantischen Monatsblätter für innere Zeitgeschichte. In 1856-57 he worked as a mediator between Prussia and Switzerland in regards to the Neuenburger Handel (Neuchâtel affair).