Schleswig–Holstein question

Holstein, just on the other side of the Danish border from Schleswig, was in the Middle Ages a fief of the Holy Roman Empire.

The Treaty of Ribe, agreed to by the Danish King in order to gain control of both states, seemed to indicate that Schleswig and Holstein were to remain united, though that interpretation was later challenged.

This was seen as a violation of the London Protocol, and it led to the Second Schleswig War of 1864 and ultimately to the Duchies' absorption into the German Confederation.

[2] The underlying legal dispute over the duchies was seen as complex and somewhat obscure by contemporaries, as evidenced by a quip attributed to British statesman Lord Palmerston: "Only three people have ever really understood the Schleswig-Holstein business – the Prince Consort, who is dead – a German professor, who has gone mad – and I, who have forgotten all about it.

Following the defeat of the German Empire in World War I, the Danish-majority area of Northern Schleswig was finally unified with Denmark after two plebiscites organised by the Allied powers.

During the centuries following the Middle Ages, Low German had come to dominate in Southern Schleswig, which had originally been predominantly Danish-speaking.

Linguistically Low German immigrants constantly arrived, and previously Danish-speaking families often came to find it convenient to change languages.

One solution, which afterwards had the support of Napoleon III, would have been to partition Schleswig on the lines of nationality, assigning the Danish part to Denmark, the German to Holstein.

This idea, which afterwards had supporters among both Danes and Germans, proved impracticable at the time owing to the intractable disposition of the majority on both sides.

In Denmark it was granted less significance, and the citing widely regarded to be out of context, as it could either hint at the duchies not being separated from each other, or their not being partitioned into smaller shares of inheritance.

By Article XIX of the definitive Treaty of Vienna signed on 30 October 1864, a period of six years was allowed during which the inhabitants of the duchies might opt for Danish nationality and transfer themselves and their goods to Denmark; and the rights pertaining to birth in the provinces were guaranteed to all, whether in the kingdom or the duchies, who had been entitled to those rights at the time of the exchange of ratifications of the treaty.

This question is of great interest to students of international law and as illustrating the practical problems involved in asserting the modern principle of nationality.

Following the defeat of the German Empire in the First World War, the Allied powers organised two plebiscites in Northern and Central Schleswig on 10 February and 14 March 1920, respectively.

Elements of the Schleswig–Holstein question were fictionalised in Royal Flash, the second of George MacDonald Fraser's The Flashman Papers novels.

Danish author Herman Bang wrote of life on the island of Als in the aftermath of the Battle of Dybbøl in the Second War of Schleswig in his novel Tine, published in 1889.