The Sovereign or Grand Master is the head of the Order of the Golden Fleece. Prior to the Napoleonic wars the Grand Master was always identical with the monarch controlling the Spanish or Austrian Netherlands, although afterwards the order split into separate Austrian and Spanish branches.
The present Grand Master of the Austrian order is Karl von Habsburg; that of the Spanish order is the Felipe VI of Spain.
List of Grand Masters
References
Grand Master of the Order of the Golden Fleece Wikipedia(Text) CC BY-SA