Aagesen was educated for the law at Christiania ( now Oslo ) and Copenhagen, and interrupted his studies in 1848 to take part in the First Schleswig War, in which he served as the leader of a reserve battalion.

In 1863 – 64, disputes between Prussia and Denmark grew over Schleswig, which was not part of the German Confederation, and which Danish nationalists wanted to incorporate into the Danish kingdom.

Germany was to cede Alsace-Lorraine, Eupen-Malmédy, North Schleswig, and the Memel area.

The city of Schleswig was later founded on the other side of the Schlei, and gave the duchy its name.

The site of Hedeby is located in the Duchy of Schleswig, which was traditionally the personal territory of the kings of Denmark.

Northern Schleswig until 2006 was South Jutland County.

Succession to the duchies of Schleswig and Holstein was disputed ; they were claimed by Christian IX ( Frederick VII's heir as King ) and by Frederick von Augustenburg ( a German duke ).

When Denmark refused, Austria and Prussia invaded, commencing the Second war of Schleswig and Denmark was forced to cede both duchies.

As a result of the Peace of Prague ( 1866 ), the German Confederation was dissolved ; Prussia annexed Schleswig, Holstein, Frankfurt, Hanover, Hesse-Kassel ( or Hesse-Cassel ), and Nassau ; and Austria promised not to intervene in German affairs.

Hedeby, which lay near the modern city of Schleswig in Schleswig-Holstein, was pretty centrally located and could be reached from all four directions over land as well as from the North Sea, the Atlantic Ocean, and the Baltic Sea.

It is unclear if Wulfstan was English or indeed if he was from Hedeby, in today's northern Germany near the city of Schleswig.

This number does not include the subdivisions of the Duchy of Schleswig, which was only under partial Danish control.

Though the status quo was restored, the conflict lingered on and on 1 February 1864 the German Confederation, i. e. Prussian and Austrian troops crossed the Eider sparking off the Second Schleswig War, after which Denmark had to cede Schleswig and Holstein according to the Treaty of Vienna.

After the Austro-Prussian War of 1866, victorious Prussia took control over all Schleswig and Holstein but was obliged by the Peace of Prague to hold a referendum in predominantly Danish-speaking Northern Schleswig, which it never did.

Not until the German defeat in World War I the Schleswig Plebiscites were decreed by the Treaty of Versailles, after which the present-day German-Danish border was drawn taking effect on 15 June 1920, dividing Schleswig in a southern and northern part and leaving a considerable Danish and German minority on both sides.

The title Duke of Schleswig was inherited in 1460 by the hereditary kings of Norway who were also regularly elected kings of Denmark simultaneously, and their sons ( unlike Denmark which was not hereditary ).

Following the Protestant Reformation when Latin was replaced as the medium of church service by the vernacular languages, the diocese of Schleswig was divided and an autonomous archdeaconry of Haderslev created.

This created a new cultural dividing line in the duchy because German was used for church services and teaching in the diocese of Schleswig and Danish was used in the diocese of Ribe and the archdeaconry of Haderslev.

Schleswig was consequently granted to Count Gerhard, being the leader of one of the three lines of the Schauenburg dynasty.

In 1721 all of Schleswig was united as a single Duchy under the King of Denmark, and the Great Powers of Europe confirmed in an international treaty that all future Kings of Denmark should automatically become Duke of Schleswig and Schleswig would consequently always follow the same line of succession as the one chosen in the Kingdom of Denmark.

Among the most advanced systems of old Germanic law of the time, in the 13th and 14th centuries, Magdeburg rights were granted to more than a hundred cities, in Central Europe apart from Germany, including Schleswig, Bohemia, Poland, Belarus, especially in Pomerania, Prussia, Lithuania ( following the Christianization of Lithuania ), Ukraine, and probably Moldavia.

In 1386, Queen Margaret I of Denmark, younger daughter of Valdemar IV of Denmark and Helvig of Schleswig, granted Schleswig as a hereditary fief under the Danish crown to Count Gerhard VI of Holstein-Rendsburg, grandson of Gerhard III, provided that he swore allegiance to her son King Oluf, although Schleswig actually still was held autonomously by the Count of Holstein-Rendsburg.

On 5 March 1460 Christian granted a coronation charter ( or Freiheitsbrief ), issued first at Ribe ( Treaty of Ribe,, ) and afterwards at Kiel, which also repeated that Schleswig and Holstein-Rendsburg must remain united " dat se bliven ewich tosamende ungedelt " ( Middle Low German or Low Saxon, i. e. that they remain for ever together undivided ).

Following the Austro-Prussian War of 1866, section five of the Peace of Prague stated that the people of Northern Schleswig should be granted the right to a referendum on whether they would remain under Prussian rule or return to Danish rule.

Although there was, as a result, a Danish minority in Southern Schleswig and a German minority in Northern Schleswig, the minorities were granted rights to practice their language and culture, to such a degree that the division and minorities are not a political issue between Denmark and Germany.

Second, all the old rights granted upon the chapels and House of God in Schleswig, Ribe, and Haderslev were given by the kings of the Realm.

On 5 March, Christian granted a coronation charter ( or Freiheitsbrief ) which repeated that Schleswig and Holstein must remain united dat se bliven ewich tosamende ungedelt.

The Schleswig lands north of the Eider river and the Bay of Kiel had been a fief of the Danish Crown since the Early Middle Ages.

Denmark was long in disputes with Sweden over control of Skånelandene ( Scanian War ) and Norway, and in disputes with the Hanseatic League over the duchies of Schleswig ( a Danish fief ) and Holstein ( a German fief ).

In 1544 the elder three brothers partitioned Holstein ( a fief of the Holy Roman Empire ) and Schleswig ( a Danish fief ) in an unusual way, following negotiations between the brothers and the Estates of the Realm of the duchies, which opposed a factual partition.

In 1460 King Christian also became Duke of Schleswig, a Danish fief, and Count of Holstein, a Saxe-Lauenburgian subfief within the Holy Roman Empire.

When the Holstein-Rendsburg line of the Schauenburg counts became extinct with the death of Adolf VIII of Holstein-Rendsburg ( and in personal union as Adolf I Duke of Schleswig ) in 1459, Christian I of Denmark inherited – from his maternal uncle Adolf I – the Duchy of Schleswig, a Danish fief.

In 1544 they partitioned the Duchies of Holstein ( a fief of the Holy Roman Empire ) and of Schleswig ( a Danish fief ) in an unusual way, following negotiations between the brothers and the Estates of the Realm of the duchies, which had constituted in 1460 by the Treaty of Ribe and strictly opposed a factual partition.

The Duchy of Schleswig, or Southern Jutland ( Sønderjylland ), had been a Danish fief, though having been more or less independent from the Kingdom of Denmark during the centuries, similarly to Holstein, that had been from the first a fief of the Holy Roman Empire, originating in the small area of Nordalbingia, in today western Holstein, inhabited then mostly by Saxons, but in 13th century expanded to the present Holstein, after winning local Danish overlord.

In 1439, the new Danish king Christopher III ( also known as Christopher of Bavaria ) bought the loyalty of count Adolphus VIII of Holstein-Rendsburg by granting him the entire Duchy of Schleswig as a hereditary fief but under the Danish crown.

Regarding Schleswig the arrangement seems at first rather odd, since Schleswig was a fief under the Danish crown, thus making the Danish king his own vassal.

Christian III, John II the Elder and Adolf partitioned the Duchies of Holstein ( a fief of the Holy Roman Empire ) and of Schleswig ( a Danish fief ) in an unusual way, following negotiations between the brothers and the Estates of the Realm of the duchies, which opposed a factual partition, referring to their indivisibility according to the Treaty of Ribe.

The Duchy of Schleswig was originally an integrated part of Denmark, but was in medieval times established as a fief under the Kingdom of Denmark, with the same relation to the Danish Crown as for example Brandenburg or Bavaria had to the Holy Roman Emperor.

The short version is: Schleswig was either integrated in Denmark or a Danish fief, and Holstein was a Holy Roman Imperial fief.

The duchy of Schleswig was legally a Danish fief and not part of the Holy Roman Empire or, after 1815, of the German Confederation ( German: Deutscher Bund, Danish: Tysk Forbund ), but the duchy of Holstein was a Holy Roman fief and a state of both the Empire and later the German Confederation of 1815 – 1866.

Christian inherited Holstein and Schleswig after a short " interregnum " as the eldest son of the sister of late Duke Adolf VIII, Duke of Schleswig ( Southern Jutland ) and Count of Holstein, of the Schauenburg fürst clan, who died 4 December 1459, without children.

King of Denmark, Sweden, Norway, the Wends and the Goths, Duke of Schleswig, Holstein, Stormarn and Dithmarschen, Count of Oldenburg and Delmenhorst

In 1386 King Oluf II of Denmark and his mother-regent, Queen Margaret I, enfeoffed in Nyborg Gerhard VI, Count of Holstein-Rendsburg and his cognatic successors with the Duchy of Schleswig.

On the death of King Valdemar's descendant Eric VI of Denmark in 1319, Christopher II of Denmark attempted to seize the Duchy of Schleswig, the heir of which Duke Valdemar V ( as of 1325 ) was a minor ; but Valdemar's guardian and uncle, Gerhard III, Count of Holstein-Rendsburg ( 1304 – 1340 ), surnamed the Great and a notable warrior, drove back the Danes and, Christopher having been expelled, succeeded in procuring the election of Duke Valdemar to the Danish throne ( as Valdemar III as of 1326 ), while Gerhard himself obtained the Duchy of Schleswig.

Gerhard VI died in 1404, and soon afterwards war broke out between his sons and Eric of Pomerania, Margaret's successor on the throne of Denmark, who claimed South Jutland as an integral part of the Danish monarchy, a claim formally recognised by the emperor Sigismund in 1424, it was not till 1440 that the struggle ended with the investiture of Count Adolphus VIII, Gerhard VI's son, with the hereditary duchy of Schleswig by Christopher III of Denmark.

Under the administration of the Danish prime minister Count Bernstorff, himself from Schleswig, many reforms were carried out in the duchies, for example, abolition of torture and of serfdom ; at the same time Danish laws and coinage were introduced, and Danish was made the official language for communication with Copenhagen.

The Danish Duke of Schleswig acquired it through a purchase in 1268, and in 1340 it was transferred to the Count of Holstein at Rendsburg of the House of Schauenburg.

The representatives of Schleswig and Holstein ( nobility and some delegates of the Estates ) convened in Ribewhere, on 5 March 1460, the succession was confirmed to Christian I of Denmark, the eldest nephew of the late Duke of Schleswig and Count of Holstein-Rendsburg.

He was also an agnatic descendant of Hedwig of Schauenburg ( countess of Oldenburg ), mother of the first King Christian I of Denmark, whose sons were the " Semi-Salic " heirs of her childless brother Count Adolf VIII of Holstein, who died in 1459, the last Schauenburg Duke of Schleswig and Count of Holstein.

The Treaty of Ribe ( mening The Ribe letter ; ) was a proclamation at Ribe made by King Christian I of Denmark to a number of Holsatian nobles enabling himself to become Count of Holstein and regain control of Denmark's lost Duchy of Schleswig ( Danish: Sønderjylland, i. e. South Jutland ).

The proclamation was issued in 1460 and established that the King of Denmark should also be Duke of Schleswig and Count of Holstein.

In 1386, Queen Margaret I of Denmark, the younger daughter of Valdemar IV of Denmark and Helvig of Schleswig, gave Schleswig as a hereditary fief under the Danish crown to Count Gerhard VI of Holstein-Rendsburg, provided that he swore allegiance to her son King Oluf.