Adolf VIII, the last Count of Holstein-Rendsburg…
1474 CE
Adolf VIII, the last Count of Holstein-Rendsburg and Duke of Schleswig, had died in 1459 without heirs.
As Schleswig had been a Danish fief, it had to fall back to King Christian I of Denmark, who, himself a nephew of Adolf, also sought to enter into possession of Holstein.
He was backed by the local nobility, who supported the continued common administration of both lands and by the 1460 Treaty of Ribe proclaimed him as the new Count of Holstein.
The comital Holstein lands south of the Eider River had officially remained a mediate fief held by the Ascanian dukes of Saxe-Lauenburg.
Emperor Frederick III In 1474 confers Imperial immediacy to Christian by elevating him to a Duke of Holstein.