Following the war, he founded the Italian Unionist Movement, which advocated for the annexation of Italy by the United States.

This work is a thorough review of the natal sex ratio, looking at past theories and at how new hypothesis fit the statistical data.

He founded the statistical journal Metron in 1920, directing it until his death; it only accepted articles with practical applications.

Gini was throughout the 20s a supporter of fascism, and expressed his hope that Nazi Germany and Fascist Italy would emerge as victors in WW2.

[7][8] Milestones during the rest of his career include: On October 12, 1944, Gini joined with the Calabrian activist Santi Paladino, and fellow-statistician Ugo Damiani to found the Italian Unionist Movement, for which the emblem was the Stars and Stripes, the Italian flag and a world map.

[1] Gini shared the view held by Oswald Spengler that populations go through a cycle of birth, growth, and decay.

[10] Gini's organicist theories of nations and natality are believed to have influenced policies of Italian Fascism.