The Concert of The Hague, signed on 21 May 1659, was an outline of the common stance of England, France and the Dutch Republic regarding the Second Northern War. The powers agreed that the Swedish Empire and Denmark–Norway should settle for a peace treaty based on the Treaty of Roskilde, including free navigation through The Sound and the Baltic Sea based on the Treaty of Elbing. The subsequent Dano-Swedish Peace of Copenhagen largely followed the terms dictated by the Concert of the Hague.