The Great Powers, angered by the Neuchâtel…

The Great Powers, angered by the Neuchâtel rebellion, formally acknowledge the rights of Frederick William IV in Neuchâtel in the London Protocol of 1852, signed on May 8 in the wake of the first War of Schleswig, but with the proviso that Prussia shall do nothing to assert them without their concurrence.

The Protocol affirms the integrity of the Danish federation as a "European necessity and standing principle".

Accordingly, the duchies of Schleswig (a Danish fief) and Holstein, and Lauenburg (German fiefs) are joined by personal union with the King of Denmark.

For this purpose, the line of succession to the duchies is modified, because Frederick VII of Denmark remains childless and hence a change in dynasty is in order. (The originally conflicting protocols of succession between the duchies and Denmark would have stipulated that, contrary to the treaty, the duchies of Holstein and Lauenburg would have had heads of state other than the King of Denmark.)

Further, it is affirmed that the duchies are to remain as independent entities, and that Schleswig will have no greater constitutional affinity to Denmark than Holstein.

The major powers primarily want to ensure, by guaranteeing Denmark's territorial integrity, that the strategically significant port of Kiel will not fall into Prussian hands.