The district was part of the Holy Roman Empire. After the Napoleonic wars the area went to Prussia, which in 1816 created the district as part of its Rhineland province. From 1936-1945 it was called Saarlautern, when the Nazi government tried to exchange the French name for a German one.
The checked black-and-white top part of the coat of arms is taken from the coat of the Hohenzollern, to remember that the area belonged to the German Empire (which was ruled by the Hohenzollern dynasty) directly. The bottom part is the coat of arms of the Lorraine, as Saarlouis belonged to Duchy of Lorraine 1100-1766. The star stands for the French fortress of Saarlouis, the origin of the city, which was build in a star form. The fleur-de-lis comes from the coat of arms of the city Saarlouis.