The regiment is part of the Italian army's infantry corps and operationally assigned to the Mechanized Brigade "Aosta".

In 1859 the brigade fought in the Second Italian War of Independence, for which its two regiments were decorated with a Gold Medal of Military Valor and then participated in the repression of Brigandage in Southern Italy in 1861 and in Aspromonte in 1862.

At the time the 5th Infantry Regiment consisted of three battalions, each of which fielded four fusilier companies and one machine gun section.

[7] On 3 July 1915, the 5th Regiment was sent to Sella Nevea and Raccolana Valley, to support the troops of the 4th Army Corps that attacked the Austrian stronghold of Plezzo.

[7] In early March 1916, the 5th and 6th Regiment "Aosta" assembled in Conca di Plezzo, before being deployed on the right bank of Isonzo river and on the slopes of Mount Kukla.

A few days after the end of the Fifth Battle of the Isonzo, on 19 March 1916, the Austrians, preceded by a destructive bombardment, attacked by surprise and managed to overcome the Italian defenses at the bottom of the valley.

Particularly intense was the battle around Zagora, where the Italian troops attacked the Monte Santo, defended by the 62nd Austrian Division.

From November 1916 until the end of the year, the fusiliers of the Brigade "Aosta" remained entrenched between Pecinka and Dosso Faiti.

[7] The regiment also fought in Ravnilaz, on the Carso, in Doberdò, Cima Debeli, on the Col Moschin and Cà d'Anna, on the Montello, and in Vittorio Veneto.

On 1–6 August 1943 the Aosta was badly mauled by US Army troops during the Battle of Troina in the North of the island.

The remnants of the division in Trento were disbanded by invading German forces after the announcement of the Armistice of Cassibile on 8 September 1943.

[4] On 20 September 1944 the Italian Co-Belligerent Army formed in Sicily the III and IV internal security brigades with the regiments of the disbanded 47th Infantry Division "Bari".

On 31 August 1992 the battalion was elevated to 5th Mechanized Infantry Regiment "Aosta" without changing size or composition.