The Evolution of international law is, nonetheless, connected with this wider context. From the seventeenth century onwards a sense of the legal immunity of states from prosecution in the courts of another state for actions performed in pursuance of national policy becomes manifest. States, meanwhile, came conventionally to be seen as the appropriate parties to international law,before which they have juridical equality. In Oppenheim's fomulation, international law is and should remain law between states only and exclusively.