The Vatican Post commemorated the first centenary of the death of Pope Pius IX (1792-1878) with a multicolor series of three values. It issued the stamps on May 9, 1978, the opening day of "Pope Pius IX Philatelic Exhibition," which was held in Rome.
To commemorate the centenary and the philatelic history of the Pontifical States, the exhibition took place May 9-14, 1978. The Italian Philatelic Association of Rome, with the cooperation of the Vatican and Italian Postal Administrations, sponsored the exhibition. The exhibits were appropriately named the "Alberto Diena Philatelic Exhibition," homage to the late Dr. Diena, an eminent scholar of all aspects of Pontifical States philately. The exhibition was devoted exclusively to rare stamps and covers of the Pontifical States period.
Although the three values have a basic common design, consisting of a floral design incorporating two scrolls with the inscription "Pius IX 1878-1978," each stamp's central design varies. The 130-lire stamp shows the pope's coat of arms. The 170-lire stamp shows the pope's seal, used in the "Bull" defining the Dogma of the Immaculate Conception. The 200-lire stamp features a portrait of the pope from a painting in the Vatican Apostolic Library. "POSTE VATICANE" appears under the floral design at the bottom of each stamp, and the value is located directly above the word "POSTE."
The stamps, designed by P.N. Argittu, are vertical in format, measure 30 x 40 mm, and have a perforation of 13 1/4 x 14. The total printing amounted to 1,150,000 complete sets, distributed in sheets of forty stamps. The State Polygraphic Institute, Rome, printed the stamps in rotary photogravure on white glossy paper.
Lopreiato, Joseph. "Pope Pius IX - Death Centenary 1878 - 1978." Vatican Notes 27, no. 2 (September - October 1978): 7.
Lopreiato, Joseph. "Exhibition Honors Pius IX and Dr. Alberto Diena." Vatican Notes 27, no. 2 (September - October 1978): 8.