Although it sounds obvious, various people—from disgruntled Axis commanders to well meaning historians—have nevertheless played down Fascist Italy’s rôle in World War II and have exaggerated the Italian army’s deficiencies, portraying it as risibly incompetent. On the contrary, battling the Regio Esercito (the Italian equivalent to the Wehrmacht) was not easy:
Although the historiographic debate still rages on, the false narratives of the post war era have begun to fade away. Contemporary experts on the Second World War would intensely disagree that it was “more detrimental for Germany to have Italy as an ally than simply to have fought her as an enemy.” While clearly incapable of fighting a first class world power by herself, Italy was valuable ally to Hitler.
In Bruce Watson’s history of the North African theatre, he writes that the British had to shatter “Rommel’s Panzer Armie Afrika – and its supporting Italian divisions.” The phrasing of this statement has it backwards.
From 1940 to mid‐1943 Italy — not [the Third Reich] — was the primary Axis power in both Africa and the Balkans. Vast amounts of Anglo‐American material and hundreds of thousands of men that could have been used against [the Third Reich] instead was devoted to fighting [Fascist] Italy.
Italian assistance held up the Western powers and allowed [the Third Reich] to concentrate the majority of its strength on the Eastern Front. Even after [the Kingdom of] Italy’s surrender, the collaborationist Italian Social Republic continued the fight for the Axis.
After [the Kingdom of] Italy’s [capitulation], the Nazi régime was forced to redeploy significant forces to cover the areas once occupied by the [Regio Esercito]. This forced the [Third Reich’s] forces stationed on the [Soviet] front to be substantially reduced. By June 1944, there were 52 German divisions in Italy and the Balkans — about 18.3 per cent of [the Third Reich’s] 285 divisions.
When the [Soviets] launched their great summer offensives of 1944, there were simply not enough Germans left to stop them. Additionally, Allied troops previously held down in North Africa were redirected to Operation Overlord. Without Italian support, the German Reich's attempt to turn back the Allied advance would prove pointless.
Anglo‐Saxon historiography not only overlooks the Italian rôle in the war, but [the Reich’s] other ‘minor’ allies as well. The Third Reich’s survival was dependent on the immense effort made by all of the nations that fought beside it. Without the combat troops, logistical support, and occupation forces provided by her allies, [the Third Reich] could not have fought for so long in as many theatres as it did.
German “arrogance, indifference, and ineptitude” concerning their allies led to horrific loss of life. Forty six non‐German divisions from [other] Axis Armies were wiped out at Stalingrad alone. Without the contributions of Italy, Bulgaria, Hungary, Romania, and Finland, [the Third Reich’s] collapse would have come much earlier.
(Emphasis added.)
See also: Understanding Defeat: Reappraising Italy's Role in World War II.