Cox's was the successor to a small seamstress shop established in 1884 by Mary Ann Cox in McKeesport, Pennsylvania. By the 1950s, the operation had grown sufficient enough that Robert Cox, grandson of Mary Ann, purchased the White Opera house at the corner of Fifth Avenue and Market Street in the downtown business district of McKeesport and demolished it to build a flagship department store. The modern four-story department store, built in the International Style, opened in 1955. A large concrete medallion of William Shakespeare that had served as a centerpiece of the opera house was retained and displayed on the lower level of the department store.