The first edition was published serially between 1929 and 1936. In all, 35 volumes were published, plus one index volume. The set contained 60,000 articles and 50 million words. Each volume is approximately 1,015 pages, and 37 supplementary volumes were published between 1938 and 2015. The director was Giovanni Gentile and redactor in chief Antonino Pagliaro.
Most of the articles are signed with the initials of the author. An essay credited to Benito Mussolini entitled "The Doctrine of Fascism" was included in the 1932 edition of the encyclopedia, although it was ghost-written by Gentile.