In 1864, Prussia and Austria jointly went to war against Denmark over the duchies of Schleswig and Holstein. (a) Describe the causes and outcome of the war ...

The Danish War of 1864 was the first of Bismarck's three wars of unification. It is often studied as either a calculated first step towards German unity or an opportunistic response to events.

(a) Causes and outcome of the war against Denmark [4 marks]

• Cause: In November 1863, Denmark's new King Christian IX incorporated the duchy of Schleswig into the Danish state, violating the 1852 London Protocol, which had guaranteed the duchies' separate status.
• German Confederation response: The German Confederation demanded Denmark reverse this decision. When Denmark refused, Prussia and Austria jointly declared war in February 1864.
• Military outcome: The combined Prussian and Austrian forces defeated Denmark quickly, storming the Duppel fortifications in April 1864.
• Treaty of Vienna (October 1864): Denmark surrendered both Schleswig (to be administered by Prussia) and Holstein (to be administered by Austria).

(b) Why the dispute increased tensions between Prussia and Austria [6 marks]

• The Convention of Gastein (August 1865): This agreement divided administration of the duchies, with Prussia governing Schleswig and Austria governing Holstein, but the arrangement was geographically awkward and politically unstable.
• Geographic impracticality: Holstein was separated from Austria by Prussian territory, making Austrian administration difficult and dependent on Prussian cooperation.
• Bismarck's deliberate provocation: Bismarck manufactured disputes over the administration of the duchies, accusing Austria of mismanaging Holstein and encouraging pro-Prussian agitation there.
• The question of the duchies' future: Austria wanted the duchies to become an independent state under the Duke of Augustenburg, while Prussia aimed to absorb them. This fundamental disagreement could not be resolved peacefully.
• Austrian appeal to the German Diet: When Austria proposed referring the Schleswig-Holstein question to the German Diet (Federal Assembly), Bismarck declared this a violation of the Gastein Convention and used it as a pretext for war.
• Mutual accusations: Both powers accused each other of mismanaging their respective duchy, creating a spiral of diplomatic confrontation.

(c) How far was the Danish War a deliberate step towards unification? [10 marks]

Evidence it was deliberate:

• Bismarck used the war to test the effectiveness of the reformed Prussian army in a low-risk conflict against a weak opponent, giving him confidence for larger wars ahead.
• The division of the duchies at Gastein was arguably designed to create future friction with Austria, providing a pretext for the decisive confrontation Bismarck planned.
• By placing Prussian forces in Schleswig, Bismarck gained a strategic position between Denmark and Austria's territory in Holstein.
• He used Austrian mismanagement of Holstein as the immediate trigger for the Austro-Prussian War of 1866, which excluded Austria from German affairs permanently.
• The war established the precedent that Prussian military action could resolve 'German questions,' normalising the use of force for national purposes.

Evidence it was not entirely deliberate:

• The Danish crisis was not of Bismarck's making. King Christian IX's annexation of Schleswig was an independent event that Bismarck responded to, not something he engineered.
• Bismarck initially cooperated with Austria in a conventional great-power alliance, which suggests he had not yet decided on war with Austria.
• Some historians (notably A.J.P. Taylor) argue Bismarck was an opportunist who exploited circumstances as they arose rather than following a predetermined master plan for unification.
• German nationalist pressure to defend Schleswig-Holstein existed independently of Bismarck; any Prussian leader would have faced pressure to act.
• The alliance with Austria was standard conservative diplomacy, not necessarily a cunning trap.

Conclusion: Bismarck probably did not plan the entire sequence from the Danish War through to unification in advance. However, he skilfully exploited the Schleswig-Holstein dispute to test his army, position Prussia strategically, and create the conditions for the decisive conflict with Austria in 1866. Whether his approach was a grand plan or brilliant opportunism, the Danish War advanced Prussian interests at every stage.