To contemporary residents of the area, the term "King of Prussia" typically evokes images of the shopping mall or Valley Forge Exit on the Pennsylvania Turnpike. The mailing address (19406 zip code) comprises substantially that area of Upper Merion Township that lies between the Schuylkill Expressway and the River, and surrounding Bridgeport Boro (zip 19405).
"King of Prussia" was a popular name used by many innkeepers, mainly of German descent. There were several Inns by the name King of Prussia in the greater Philadelphia region, including one in Germantown. The Upper Merion version of the namesake Inn, and the genesis for the naming of the area, is believed to have been operated as early as 1709 and named by its Prussian founder in honor of Frederick I, who crowned himself "King in Prussia" in 1701; (other account put its origination circa 1719 by William Rees; see King of Prussia Inn, National Register documentation) by 1786, when one John Elliott was proprietor of the Inn, a village of the same name had been established in the vicinity.
In 1947 Mitchell  writes "The picturesque old inn at King of Prussia is still doing business. Its antique signboard, showing Frederick I on horseback, is traditionally ascribed to Gilbert Stuart, who is said to have painted it when he was hard up, strictly upon condition that his name should not be divulged. Whatever may be the truth of the matter, the old stucco inn, with its ancient stables and springhouse, its huge chimneys and fireplaces, and its attractive old-time atmosphere is one of Pennsylvania's best known wayside hostelries.
In August of 2002 the Inn was "moved" from Route 202 to 101 Bill Smith Boulevard by the Greater Valley Forge Chamber of Commerce; the Chamber restored the structure and located its operations there in October of 2003,