Formation On 21 July 1858,
French Emperor Napoleon III and the
Prime Minister of Sardinia Camillo Benso, Count of Cavour met in
Plombières and reached a
secret verbal agreement on a military alliance between the
Second French Empire and the
Kingdom of Sardinia against the
Austrian Empire. On 26 January 1859, Napoleon III signed the Franco-Sardinian Treaty, followed by King
Victor Emmanuel II on 29 January 1859. On 9 March 1859, Sardinia mobilized its army, followed by Austria on 9 April. On 23 April, Austria delivered an ultimatum to Sardinia demanding its demobilization. Upon Sardinia's refusal, Austria declared war on 26 April and three days later the Austrians crossed the
Ticino river into
Piedmont. Consequently France honored its alliance with Sardinia and declared war on Austria on 3 May 1859.
Third Italian War of Independence After the successful conclusion of Garibaldi's
Expedition of the Thousand the Kingdom of Sardinia annexed the
Kingdom of the Two Sicilies. On 17 March 1861, King
Victor Emmanuel II proclaimed himself King of Italy. On 1 August 1862, the two regiments of the Brigade "Reggio" ceded their 17th Company and 18th Company to help form the
66th Infantry Regiment (
Brigade "Valtellina"). During the same year the two regiments moved to
Isernia respectively
Salerno in
Southern Italy to suppress the
anti-Sardinian revolt, which had erupted in Southern Italy after the annexation of the Kingdom of the Two Sicilies. In 1916, the brigade was sent to the
Col di Lana sector, where the brigade, in cooperation with the
Brigade "Calabria", repeatedly attacked the Austro-Hungarian positions on
Monte Sief. In 1917, the brigade remained in the Col di Lana – Monte Sief sector until the
Battle of Caporetto forced the Italians to retreat behind the
Piave river. On 2 November 1917, the Brigade "Reggio" received the order to retreat to the new Italian lines. While the brigade retreated to the Piave river, the 46th Infantry Regiment's I Battalion and III Battalion formed the rearguard. On 8 November, the brigade entered the new frontline on the Piave river's Southern bank between
Pederobba and
Vidor. The next day the two battalions left behind as rearguard, were surrounded and destroyed by advancing Austro-Hungarian troops near
Vignole. From 13 to 26 November 1917, the brigade fought in the
First Battle of the Piave River. On 6 December 1917, the Brigade "Reggio" was replaced on the front by
French forces. On 12 December 1917, the brigade was sent to reinforce Italian units fighting in the
First Battle of Monte Grappa on the
Monte Grappa massif. On the Monte Grappa the brigade took up positions between
Monte Solarolo and
Monte Valderoa, where on 17 December 1917, the 45th Infantry Regiment came under heavy enemy attacks, which were all repulsed. On 28 December 1917, the brigade, which had suffered 3,074 casualties since 2 November, was sent to the rear to be rebuilt. In 1934, the 30th Territorial Division of Cagliari was renamed Military Command Cagliari – 30th Infantry Division "Sabauda" and in September of the same year the Military Command Sassari –
31st Infantry Division "Caprera" was formed. The Military Command Cagliari was based in Cagliari and responsible for the South of the island of Sardinia, while the Military Command Sassari was based in Sassari and responsible for the island's North. The same month the XXXI Infantry Brigade "Caprera" was formed and assigned to the 31st Infantry Division "Caprera". The XXX Infantry Brigade "Sabauda" then transferred the 45th Infantry Regiment "Reggio" and 59th Infantry Regiment "Calabria" to the newly formed brigade. To bring the XXX Infantry Brigade "Sabauda" back up to strength the 60th Infantry Regiment "Calabria" was reformed in
Iglesias with personnel drawn from the 45th, 46th, and 59th infantry regiments. In 1935–36 the 45th Infantry Regiment "Reggio" provided nine officers and 171 troops to units deployed to East Africa for the
Second Italo-Ethiopian War. On 15 April 1939, the 45th Infantry Regiment "Reggio" in Sassari and the 60th Infantry Regiment "Calabria" in Iglesias switched names. On the same day the XXX Infantry Brigade "Sabauda" was disbanded and the 45th Infantry Regiment "Reggio" and 46th Infantry Regiment "Reggio" were both renamed "Sabauda" and came under direct command of the 30th Infantry Division "Sabauda". The division, which also included the 16th Artillery Regiment "Sabauda", was tasked with the defense of the Southern half of Sardinia.
Recent times On 31 August 1993, the 45th Infantry Battalion "Arborea" lost its autonomy and the next day the battalion entered the 45th Regiment "Reggio". The regiment then joined the
Mechanized Brigade "Sassari" and was tasked with training the brigade's recruits.
Reactivation On 1 October 2022, the flag and traditions of the 45th Infantry Regiment "Reggio" were assigned to the Command and Tactical Supports Unit "Sassari" of the Mechanized Brigade "Sassari". On the same day the unit was renamed 45th Command and Tactical Supports Unit "Reggio". == Organization ==