This study deals with France's impact on the politics of the Hanseatic cities Lübeck, Bremen, and Hamburg and the duchies of Schleswig-Holstein-Gottorp and Mecklenburg-Schwerin between 1650 and 1730. This was a period of change in the underlying constitutional premises of the Empire. For these powers, negotiation and diplomacy became a matter of life and death, essential for safeguarding the existence of their governments.