treaty could guarantee Austria's sphere of influence in Central Europe, thus achieving Prussian hegemony in Germany and ending the dualism debate. The Schleswig-Holstein Question The first episode in the saga of German unification under Bismarck came with the Schleswig-Holstein Question. On 15 November 1863, Christian IX became king of Denmark and duke of Schleswig, Holstein, and Lauenburg, which the Danish king held in personal union. On 18 November 1863, he signed the Danish November Constitution which replaced The Law of Sjælland and The Law of Jutland, which meant the new constitution applied to the Duchy of Schleswig. The German Confederation saw this act as a violation of the London Protocol of 1852, which emphasized the status of the Kingdom of Denmark as distinct from the three independent duchies. The German Confederation could use the ethnicities of the area as a rallying cry: Holstein and Lauenburg were largely of German origin and spoke German in everyday life, while Schleswig had a significant Danish population and history. Diplomatic attempts to have the November Constitution repealed collapsed, and fighting began when Prussian and Austrian troops crossed the Eider river on 1 February 1864. Initially, the Danes attempted to defend their country using an ancient earthen wall known as the Danevirke, but this proved futile. The Danes were no match for the combined Prussian and Austrian forces and their modern armaments. The needle gun, one of the first bolt action rifles to be used in conflict, aided the Prussians in both this war and the Austro-Prussian War two years later. The rifle enabled a Prussian soldier to fire five shots while lying prone, while its muzzle-loading counterpart could only fire one shot and had to be reloaded while standing. The Second Schleswig War resulted in victory for the combined armies of Prussia and Austria, and the two countries won control of Schleswig and Holstein in the concluding peace of Vienna, signed on 30 October 1864. War between Austria and Prussia, 1866 The second episode in Bismarck's unification efforts occurred in 1866. In concert with the newly formed Italy, Bismarck created a diplomatic environment in which Austria declared war on Prussia. The dramatic prelude to the war occurred largely in Frankfurt, where the two powers claimed to speak for all the German states in the parliament. In April 1866, the Prussian representative in Florence signed a secret agreement with the Italian government, committing each state