On 13 June 1940, immediately after the outbreak of hostilities with France and the United Kingdom, he assumed the position of deputy chief of the General Staff.

[1] In 1918 Soddu went to fight on the Western Front in France, becoming commanding officer of the III Battalion, 52nd Infantry Regiment, a part of the Alpi Brigade in the 8th Division of the II Army Corps in July 1918.

He distinguished himself on the Western Front, receiving two Silver Medals of Military Valour and a War Merit Cross from Italy and the Legion of Honour from France.

[5] In an official report, Soddu stated that there was no alterative to an offensive toward Egypt "because a defensive attitude on the eastern frontier would favor the concentration of English troops."

In an accompanying personal note, however, he added that a serious offensive plan could only be implemented with the "immediate" availability in Libya of sufficient forces to carry it out.

[1] Italy initially remained neutral in World War II, which began with Nazi Germany′s invasion of Poland on 1 September 1939.

[1] On 31 March 1940 he received a secret memorandum written by Prime Minister Benito Mussolini in which Mussolini announced his intention to enter World War II alongside Nazi Germany against France and the United Kingdom; this highly confidential memorandum was delivered to King Victor Emmanuel III that same day and subsequently to the Minister of Foreign Affairs, Galeazzo Ciano; the Chief of the General Staff, Marshal of Italy Pietro Badoglio; the Chief of Staff of the Royal Army, Marshal of Italy Rodolfo Graziani; the Chief of Staff of the Regia Marina ("Royal Navy") Ammiraglio d'Armata ("Admiral of the Navy") Domenico Cavagnari; the Chief of Staff of the Regia Aeronautica ("Royal Air Force"), Generale di divisione aerea ("Divisional General of the Air") Francesco Pricolo; the Minister of Italian Africa Attilio Teruzzi; and the secretary of the National Fascist Party, Ettore Muti.

On 13 June 1940, Soddu assumed additional duties as deputy chief of the Supreme General Staff[1][3] and commander of the Armata Territoriale ("Territorial Army").

For his part, Soddu, who as a hobby and part-time job composed musical scores for film soundtracks for the Italian film studio Cinecittà, often retreated for hours at a time to seek solace in composing music,[10] leaving his subordinates leaderless as Italian forces suffered continued setbacks in Greece and Albania.

With a force of four divisions and one brigade, the Greeks attacked the northwestern sector of the Macedonian front, held by Italian troops stationed along the course of the river Devoll, concentrating in particular between the Morova massif and Mount Ivan, with the objective of seizing Korçë, Albania.

The conquest of the city led to public demonstrations of jubilation in the streets in Greece and had major political and military repercussions in Italy.

[16] Geloso, commanding the 11th Army, proposed that the Epirus front, to avoid a possible encirclement, also retreat 60 kilometres (37 mi) to the north of Sarandë (Italian: Santi Quaranta) and Gjirokastër.

Soddu′s removal from command stemmed in part from his practice of dabbling in composing film soundtracks even in wartime, which Mussolini found inappropriate.

[20] The Fascist politician Giovanni Preziosi attacked Soddu harshly between December 1944 and March 1945 in the journal La vita italiana, accusing him of being a Freemason and of having purposely sabotaged the military campaign in Greece in 1940–1941.

[22] In addition to his hobby of composing music for films, he developed a reputation during his career for having an unusual fondness for fine food and wine.