Denmark cedes not only the German Duchy of Holstein but also the whole Duchy of Schleswig. Towards the end of the Great Migrations of the Germanic peoples which began around A.D. 250, the Saxons who had come from the area around the northern Elbe River had settled in central and western Holstein. Other areas, such as the City of Eckernförde and the Danish Wold, are mortgaged in favour of the Holsteiners. The arms did not change during the many territorial changes of Holstein. Holstein Herzogtum ( allemand) Hertugdømmet Holsten ( Danemark) 1474-1864: Ensign civile. When it becomes evident that the Danish King will remain without male heir, hereditary disputes arise even prior to his death. Later Dithmarschen became part of the Duchy of Holstein. It is little wonder that Palmerston, the English Prime Minister, is reported to have said: “There are only three men who have ever understood the Schleswig-Holstein Problem: one was Prince Albert, who is dead; the second one was a German professor, who became insane. In 1581 the Duchy of Schleswig-Holstein was divided into a royal part, the King of Denmark being duke, and a "ducal part", known as Schleswig-Holstein-Gottorp (Gottorp was the residence of the duke). In 1803 it became an exclave of the Duchy of Oldenburg (which confusingly has nothing to do with the Holsteinian city of Oldenburg).

Schleswig-Holstein-Gottorp. King Christian’s objective of this arrangement is to ensure the retention of Holstein, but the effect is that the Danish province of Schleswig becomes dissolubly linked to the German province of Holstein. However, his attack on the town of Visby and his conquest of the Island of Gotland results in a state of war with the Hanseatic League and with Sweden and Norway. The Treaty of Bordesholm of 1522 stipulates that Schleswig and Holstein will remain neutral in the war against Sweden. England attacks Copenhagen in 1807, causing the Danes to enter into alliance with Napoleon’s France. The explanation ran somewhat like this: Except for the Pinneberg line, all other counties are now under the control of descendants of the Rendsburg line. After further wars with the Slavs who are defeated around 1090, Duke Lothar of Saxony invests Count Adolf of Schauenburg with Holstein and Stormarn. Since this is the cause of uncertainties and extensive disputes in matters of inheritance, and leads to irregularities in the maintenance of debt and other contractual instruments, We consider it to be useful and good to see to the introduction of permanent family names.

Accordingly, since 1290 there are five ruling branches of the House of Schauenburg, named after the locations of their respective strongholds: Segeberg, Kiel, Plön, Pinneberg and Rendsburg. De 1490 à 1523 et à nouveau 1544-1773 le duché a été réparti entre les différentes branches Oldenburg, notamment les ducs de Néanmoins, les terres Holstein comtale au sud de la rivière Eider est resté officiellement un fief médiate détenu par les En 1544, les duchés du Schleswig Holstein et ont été répartis en trois parties entre le petit - fils de Christian En outre, des parties importantes de Holstein ont été administrées conjointement par les ducs de Holstein-Glückstadt et les ducs de Holstein-Gottorp, principalement sur la Ses territoires restants forment le duché de Holstein-Gottorp, administré de Le roi du Danemark en sa qualité de duc de Holstein, et duc de Schleswig, nommé In contrast, the German population – supported by Prussia and Austria – argue that the duchies should be ruled by the Duke of Augustenburg. A decree of 1665 stipulates that those entitled to hereditary succession will also succeed to his Holstein possessions. Denmark rejects this ultimatum. When Duke Adolf VIII dies in 1459 without an heir, no other Count can advance a claim on both duchies. In the Battle of Bornhöved on July 22, 1227, the Danish King Waldemar II is defeated. Count Gerhard is killed in battle in Dithmarschen in 1404; inheritance disputes arise. Danes and Jutes had moved to southeastern Schleswig, and the Frisians had populated western Schleswig and the islands in the North Sea. The new border between Denmark is set at the Kongeå (Königsau in German), a small river some 50 km north of Flensburg. This increases nationalistic tensions between the “Danish” and the “German” inhabitants of Schleswig Holstein. King Christian I of Denmark (who is a descendant of the counts of the House of Oldenburg and who was elected King of Denmark in 1448) intervenes by calling the nobility to Ripen [Ribe] where he is elected as Duke Adolf’s successor on March 2, 1460. Thus, Holstein becomes entitled to its own constitution and a commission is formed in August, 1816 to draft one. He is followed in 1533 by his son as Christian III who abolishes the Catholic church in Holstein, Schleswig, Denmark and Norway, and establishes the Reformation by law. To understand the causes of the various wars and conflicts in Schleswig-Holstein, it is necessary to understand its political developments. After 1815 Holstein was incorporated in the newly formed German Confederation. On July 8, 1846 the King issues an “open letter” declaring that the Danish succession laws are valid for Schleswig as well.

Le duché de Holstein en 1789 . The eastern boundary was formed by a line running from the Kiel Fjord via the Schwentine river and the middle Trave river to Boizenburg. During the decades of Prussian rule within the German Empire, authorities attempted a Germanization policy in the northern part of Schleswig, which remained predominantly Danish. Count Gerhard III is appointed guardian and regent, and governs the kingdom.