[1] During the First World War he fought with the Third Army on the Karst Plateau, distinguishing himself in the battles of the Isonzo and rising in rank from second lieutenant to major.

In June 1918 he was decorated with a Silver Medal of Military Valor personally presented to him by the commander of the 3rd Army, Emanuele Filiberto of Savoy-Aosta for the courage shown in defending the Candelù sector during the First Battle of the Piave.

[2][1] He was promoted to major general on 1 January 1942, and on 22 February 1942 he was transferred to the command of the 44th Infantry Division Cremona, which he left on 9 November, being replaced by his deputy Gioacchino Solinas.

After the second battle of El Alamein he was immediately transferred to Tunisia and, after a short period at the disposal of the XXI Army Corps, on 22 November he became commander of the 136th Armored Division "Giovani Fascisti", participating in the battles of Medenine, of the Mareth Line, of Wadi Akarit and of Enfidaville until 12 April 1943, when he was repatriated following to the death in combat of his only son Luigi, a pilot in the Regia Aeronautica, being replaced by General Guido Boselli at the head of the "Giovani Fascisti".

Sozzani was then assigned to the Ministry of War; on 9 June 1943 he was awarded the title of Knight of the Military Order of Savoy.