Final answer:
Giovanni Giolitti's first resignation from office is not detailed in the provided information. The content focuses on events related to Mussolini, Italian unification in the 19th century, and the aftermath of World War I.
Step-by-step explanation:
The first resignation of Giovanni Giolitti from office took place long before World War II and the rise of Mussolini. Giolitti, an Italian statesman, was prime minister five times between 1892 and 1921. However, the information provided does not directly address the first time Giolitti resigned. Instead, it focuses on later historical periods, such as the actions of Benito Mussolini and the Grand Fascist Council's decision in July 1943 to remove Mussolini from power, the establishment of a government under Marshal Pietro Badoglio, and the subsequent negotiations with the Allies. It also touches on period events during the unification of Italy under leaders like Giuseppe Garibaldi and Count Camillo di Cavour in the 19th century, and the impact of Mussolini's fascist government after World War I. None of these details relate to Giovanni Giolitti's first resignation.