Frusci fought on the southern front for General Rodolfo Graziani during the Second Italo-Abyssinian War. In April 1936, during the Battle of the Ogaden, Frusci commanded the center column of three columns attacking the Ethiopian "Hindenburg Wall".
During World War II, Frusci was a Lieutenant-General and the Italian Governor of Eritrea. As a Lieutenant-General, he commanded Italian forces fighting in Eritrea during the East African Campaign. In mid-1940, Frusci oversaw the initial Italian attacks into the Sudan Later in 1940, even when ordered to do so, he chose not pull out of the Sudan. Instead, he rebuffed the initial efforts of British and Commonwealth forces to retake the border towns. In November, an assault on Gallabat was stopped short of its goals, the attacking force was hit hard from the air, and the position was re-taken by Italian ground forces.
With the fall of Eritrea, Frusci became a prisoner of war.
- Inspector of Infantry
- Colonel, Ogaden border region command, Italian Somaliland – 1935 to 1936
- Deputy General Officer Commanding, (Corpo Truppe Volontarie), Spain – 1936 to 1937
- General Officer Commanding, 20th Division Friuli, Spain – 1937 to 1938
- General Officer Commanding, XX Corps, Libya – 1938 to 1939
- Governor of Amhara, Ethiopia – 1939 to 1941
- Governor of Eritrea – 1940 to 1941
- General Officer Commanding, Eritrean Army, East Africa – 1940 to 1941
- Prisoner of War – 1941