Around the year 1080 King Henry IV of Germany vested one Count Siegbert in the Saargau with the Carolingian Kaiserpfalz at Wadgassen on the Saar River and further possessions held by the Bishops of Metz in the Bliesgau as well as in the adjacent Alsace and Palatinate regions as a fiefdom.

In the course of the fierce Investiture Controversy, the rise of the comital dynasty continued with the appointment of Siegbert's son Adalbert as Archbishop of Mainz in 1111, and in 1118 his elder brother Frederick was first mentioned with the title of a "Count of Saarbrücken".

Simon III of Saarbrücken, count from 1207, was a loyal supporter of the Imperial House of Hohenstaufen and of Philip of Swabia.

Vested with the Lordship of Vaucouleurs as well with the title of a Grand Butler of France, he nevertheless had to pawn large parts of his possessions to Archbishop Baldwin of Trier.

Though after his death in 1544 the county was split into three parts, the three lines (Ottweiler, Saarbrücken proper and Kirchheim) were all extinct in 1574 and all of Nassau-Saarbrücken was united with Nassau-Weilburg until 1629.

In 1793 the territories of Nassau-Saarbrücken were occupied (along with the rest of the Left Bank of the Rhine) by the French First Republic; in 1797 Saarbrücken was annexed to the Sarre department.