The Treaty of Ribe ( meaning The Ribe letter; ) was a proclamation at Ribe made in 1460 by King Christian I of Denmark to a number of Holsatian nobles enabling himself to become Count of Holstein and gain control of the Duchy of Schleswig (Danish: Sønderjylland, i.e. South Jutland). The most famous line of the proclamation was that the Danish Duchy of Schleswig and the County of Holstein within the Holy Roman Empire, should now be, in the original Middle Low German language, Up Ewig Ungedeelt, or "Forever Undivided". The treaty The proclamation was issued in 1460 and declared that the King of Denmark should also be Duke of Schleswig and Count of Holstein. Another clause granted the nobility the right to revolt should the king break the agreement (a common feature of several medieval coronation charters). The agreement was most straightforward in regard to the future of Holstein, since King Christian I merely added the title of count to his existing titles. He was forbidden from annexing Holstein to Denmark and Holstein retained its independence and its position as an afterlehen of Saxe-Lauenburg (which, as part of the former Saxony, inherited this right), indirectly under the Holy Roman Emperor. Regarding the future of Schleswig, the agreement seems at first sight to contradict itself: the Danish king became Duke of Schleswig, a Danish fief, in effect becoming his own vassal. This arrangement should be seen as a guarantee against excessive Danish domination of the new union, whilst safeguarding against the partitioning of Holstein among Danish nobles. The most obvious result of this distinction was the exclusion of Schleswig in subsequent Danish laws, although the medieval Danish Code of Jutland (Danish: Jyske Lov) was retained as Schleswig's legal code. Another important, but much later, development was the gradual introduction of German-speaking administrators in the duchy resulting in a gradual but permanent Germanisation of the southern part of the province. German culture first spread in the cities, most probably as a result of the presence of merchants from the Hanseatic League. The process was greatly accelerated following the Lutheran Reformation, which introduced German liturgy in the churches in southern Schleswig - although the vernacular in most of this area was Danish. The major breakthrough of the process of Germanisation, however, did not occur until the end of the eighteenth century. Historical background Early history From the beginning of Danish history, the