The Electoral Palace in Koblenz, was the residence of the last Archbishop and Elector of Trier, Clemens Wenceslaus of Saxony, who commissioned the building in the late 18th century. In the mid-19th century, the Prussian Crown Prince had his official residence there during his years as military governor of the Rhine Province and the Province of Westphalia. It now houses various offices of the federal government.

William I, or Wilhelm I, was King of Prussia from 1861 and German Emperor from 1871 until his death in 1888. A member of the House of Hohenzollern, he was the first head of state of a united Germany. He was de facto head of state of Prussia from 1858, when he became regent for his brother Frederick William IV. During the reign of his grandson Wilhelm II, he was known as Wilhelm the Great.