The County of Nassau was a German state within the Holy Roman Empire from the period of the formal recognition of the countly title in 1159 until the declaration of the Duchy of Nassau in 1806 with the creation of the Confederation of the Rhine. Through succession, it had many counts ruling parts of it, mostly or completely independent of one another. After many of these counts were promoted to princely status, the County was promoted and thus was known as a Princely County or as the Principality of Nassau.