The 'Battle of Troina' was fought between Allied and Axis forces in the later stages of the 'Husky' (i) Allied seizure of Sicily as elements of Lieutenant General Omar N. Bradley’s US II Corps of Lieutenant General George S. Patton’s US 7^th Army fought to take Troina, a town in north-eastern Sicily along the Caronie mountains (31 July/6 August 1943).

The battle was centred on the numerous hills and mountains surrounding Troina, which the Germans had heavily fortified and used as bases for direct and indirect artillery fire against the US forces advancing on Messina.

On 29 July, after 20 days of combat following the 'Husky' (i) landings in south-western Sicily, it was clear to both the Allied and German high commands that Sicily was lost and that between 80,000 and 100,000 US and British troops would break through the German and Italian 'Etna-Linie' defences. Commanding the US 7^th Army, Patton had ordered Major General Terry de la M. Allen’s US 1^st Division (1^st, 16^th, 18^th and 26^th Infantry) and Major General Manton S. Eddy’s US 9^th Division (39^th and 60^th Infantry supplemented by the Free French 4ème Tabor des Goumiers marocaines) to be shifted into the valley to attack the town of Troina. Commanding the US II Corps, Bradley responded to Patton’s orders by pulling the two divisions out of the line once Troina had fallen. Troina was considered one of the main anchors of the 'Etna-Linie', and was held by Generalleutnant Eberhardt Rodt’s 15^th Panzergrenadier of General Hans-Valentin Hube’s XIV Panzerkorps and four infantry battalions of Generale di Divisione Giacomo Romano’s Italian 28a Divisione fanteria 'Aosta' within Generale d’Armata Alfredo Guzzoni’s Italian 6a Armata. The Axis forces, well sited and occupying deep trenches, had clear fields of vision over the oncoming Allied soldiers, who had little cover.

The 'Battle of Troina' began on 31 July, when the Germans repelled an advance by the 39^th Infantry, a unit of the 9^th Division temporarily attached to the 1^st Division. This was a setback which compelled Bradley and Allen to orchestrate a massive assault. Over the course of the following six days, the men of the 1^st Division, together with elements of the 9^th Division and the attached Free French Moroccan infantry battalion, 165 pieces of artillery divided among nine battalions of 105-mm (4.13-in) howitzers, six battalions of 155-mm (6.1-in) howitzers, and one battalion of 155-mm (6.1-in) 'Long Tom' guns, received major support from numerous Allies warplanes as they were locked in combat with Troina’s tenacious defenders. Control of key hill-top positions changed hands frequently, with the Germans and Italians launching more than two dozen counterattacks during the week-long battle.

The experience of Colonel John Bowen’s 26^th Infantry was fairly typical of the fighting round Troina. The regiment’s task was to outflank Troina by seizing Monte Basilio 2 miles (3.2 km) to the north of the town, and thus be in the position to sever the Axis forces' line of retreat. Bowen moved his men forward on 2 August with the support of the guns of one battalion of 155-mm (6.1-in) howitzers, four battalions of 105-mm (4.13-in) howitzers and four batteries of 155-mm (6.10in) guns. Despite the weight of fire delivered by the US artillery, the combination of German artillery fire and the difficulty of the terrain limited the regiment’s advance to 880 yards (800 m). The next morning one of the regiment’s battalions lost its bearings in the hilly terrain and wandered around ineffectually for the rest of the day. A second battalion reached Monte Basilio with relatively little difficulty, only to be pounded by Axis artillery directed from neighbouring hills. The 115^th Panzergrenadierregiment launched a counterattack to retake the mountains, but was driven back by machine gun fire.

For the next two days the men on Monte Basilio were pinned by artillery fire. Determined to hold Troina for as long as possible, the Germans reacted strongly to the threat posed by the 26^th Infantry to their line of communications. Axis pressure practically isolated the US troops on Monte Basilio from the rest of the 1^st Division, and attempts to resupply them by air were only partially successful. By 5 August, food and ammunition were low and casualties had greatly depleted the regiment, with one company mustering only 17 men fit for duty.

It was at this point that the German infantry attacked again, triggering another round of bitter fighting. During the battle, Private James W. Reese moved his mortar squad to a position from which he could effectively engage the advancing German infantry, and the squad maintained a steady fire on the attackers until it began to run out of ammunition. With only three mortar rounds left, Reese ordered his crew to the rear while he advanced to a new position and knocked out a German machine gun with the last rounds. He then picked up a rifle and continued to engage the attackers until he was killed by a barrage of fire.

The Germans evacuated Troina later that night. Hard pressed by US forces throughout the Troina sector and unable to dislodge the 26^th Infantry from its position threatening his line of retreat, Hube withdrew his badly mauled 15^th Panzergrenadierdivision toward Randazzo. As the 9^th Division took up the pursuit, the 1^st Division was rested.

While the 1^st Division fought for possession of Troina, Major General Lucian K. Truscott’s US 3^rd Division had encountered opposition at San Fratello, the northern end of the 'Etna-Linie'. Here Generalleutnant Walter Fries’s 29^th Panzergrenadierdivision and Generale di Brigata Ottorino Schreiber’s 26^th Divisione fanteria 'Assietta', which had had been allocated the most exposed section of the line, had entrenched on a ridge overlooking the coastal highway. From 3 August, Truscott’s division made repeated attempts to crack the San Fratello position, but failed to gain much ground. The strength of the German position prompted him to try to outflank it by an amphibious end run. On the night of 7/8 August, while the 3/15^th Infantry and 3/30^th Infantry seized a key hill along the San Fratello line, Lieutenant Colonel Lyle Bernard led the 2/30^th Regiment, reinforced by two batteries of the 58^th Armored Field Artillery Battalion, one platoon of medium tanks and one platoon of combat engineers, in an amphibious landing at Sant’Agata, a few miles behind San Fratello. The amphibious assault achieved complete surprise and quickly blocked the highway along the northern coast of Sicily. The Germans had selected that night to withdraw from San Fratello, without advising the Italian defenders, and most of their troops had already retired past Bernard’s position by the time the Americans arrived. Nevertheless, the 3^rd Division’s combined land and sea offensive took more than 1,000 prisoners.

Allied pressure had thus broken the 'Etna-Linie', but there would be no lightning exploitation of the victory. Taking maximum advantage of the constricting terrain and armed with a seemingly inexhaustible supply of mines, Hube withdrew his XIV Panzerkorps in orderly phases toward Messina.

Patton made a second bid to trap the 29^th Panzergrenadierdivision on 11 August, when he despatched Bernard on another amphibious 'end run', this time at Brolo. Once again Bernard’s men achieved complete surprise, but then quickly came under heavy pressure as the German units trapped by the landing tried to batter their way out. Bernard’s group proved too small to keep the Germans bottled up, and by the time Truscott’s division linked with the landing force, the bulk of the 29^th Panzergrenadierdivision had escaped.

Because of the high casualties in this fighting, Bradley had Allen and his subordinate, Brigadier Theodore Roosevelt, relieved Allen of command, which was then assumed by Major General Clarence R. Huebner.