The Duke of Mecklenburg was a descendant and the heir of two women whom legends tied to Scandinavian royal houses: The Sverker dynasty had long been extinct, having lost the throne ultimately to Eric XI.

The couple's second son duke Albert III deposed his uncle from the Swedish throne, and ascended as king.

Already when Olav IV of Norway was young and his mother Margaret was regent, the Dukes of Mecklenburg advanced their claims.

The Dukes of Mecklenburg's claim to the Norwegian throne was based on their descent from Euphemia of Sweden, granddaughter of Haakon V of Norway.

When Eric's nephew king Christopher died (before the death of the deposed Eric III of Norway), after some hiatus another magnate, Christian VIII of Oldenburg, descended in the female line from Euphemia and the Mecklenburg family (Euphemia's daughter's great-grandson), was chosen as king of Norway in 1450, this time passing over his cousin and male-line rival, Duke Henry the Fat of Mecklenburg.

The Dukes of Mecklenburg continued to regard themselves as the rightful heirs to the throne of Norway but they were unable to gain the kingdom from the Oldenburgs.

Until the late 18th century, most parts had returned to the senior branch (Schwerin), after which the patrimony was divided in two states until the very end of monarchy in Germany: These were elevated to grand duchies by recognition of the Congress of Vienna.