Liberal sentiment in Germany had always been stirred by a desire to separate Schleswig-Holstein from Denmark. The liberals called for a repudiation of international agreements by Prussia (such as the 1852 Protocol which put the Danish issue on ice),
while Bismarck declared in the Diet that he would not be a party to a breach of international obligations.
So Bismarck made an agreement with Austria, the avowed enemy of German unity, to proceed within the context of the 1852 Protocol. The two powers then sent an ultimatum to Denmark on January 16, 1864 demanding a withdrawal of the constitution of November18 (which incorporated Schleswig in Denmark) within 48 hours or face military action. Denmark, counting on the support of the European Powers, rejected the ultimatum. France hesitated to join England, which refused to act alone. So the
powers did nothing. An attempt at mediation also failed. Denmark was therefore reduced to submission by Prussian and Austrian military force.
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