Instead, after his defeat, King John recognized Alix and Peter as rulers of the Duchy.

His father was the ruler of the Duchy of Bouillon, a small principality in present day Belgium.

The Dukes of Burgundy ruler of the Duchy of Burgundy (1363-1477)

Wartislaw I (around 1091 - died August 9, 1135) was the first historical ruler of the Duchy of Pomerania and the founder of the Griffin dynasty.

Florence was the ruler of the Duchy of the Archipelago from 1362 to her death in 1371.

Margaret is wedded to Charles the Bold, ruler of the Duchy of Burgundy, the wealthiest in Europe.

This inheritance was eventually incorporated by marriage to the Gonzaga family, rulers of the Duchy of Mantua, who descend from the Palaiologoi of Montferrat.

Theodore' inheritance was eventually incorporated by marriage to the Gonzaga family, rulers of the Duchy of Mantua.

The following is a list of all rulers of the Duchy of Masovia and its parts.

In 1618, the Elector of Brandenburg became hereditary ruler of the Duchy of Prussia on the Baltic coast.