King Wilhelm I of Prussia is portrayed in this oval-vignette CDV, a format popularized in the 1860s and widely used for royal and military portrait distribution across Europe. The image presents the king in full dress military uniform, consistent with portraits produced during his reign as King of Prussia beginning in 1861 and continuing through his proclamation as German Emperor in 1871. No photographer's imprint appears on the mount.

The subject wears heavily decorated military dress with pronounced epaulettes and a high collar, beneath which an extensive array of campaign medals and orders is displayed across the chest. A large breast star is visible at lower center, and a collar chain bearing cross-form and star-form decorations hangs prominently around his neck. His characteristic receding hairline, full white side whiskers sweeping to the jaw, and upturned mustache are unmistakably rendered.

Wilhelm I served as 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 oversaw Prussian victories in the Second Schleswig War and the Austro-Prussian War before the unification of Germany was achieved following the Franco-Prussian War.

The reverse bears two inscriptions in pencil: "roi de Prusse" (King of Prussia) in a cursive hand above a second notation reading "King William."