By the outbreak of war in September 1939, the Edinburgh Fortress Engineers had been reduced to a single company (No 1 Electric Light & Works Company) in the fixed defences under
Scottish Command. However, by September 1940, it had been converted into a field engineer unit as
Edinburgh Corps Troops Royal Engineers, with 585th, 586th and 587th Army Field Companies. In July 1942, the unit was reorganised again as
1st Army Troops RE (1st ATRE) to form part of
First Army, which was preparing to take part in the
Operation Torch landings in North Africa later in the year. 585th Company was converted into an 'Army Field Park Company', which acted as a base for the field companies and held specialist equipment. 1st ATRE was joined by 561st Field Company, which had originally been part of the
38th (Welsh) Infantry Division, but left when that division was placed on a lower establishment in November 1941.
Tunisian campaign During Torch, a large part of 585th Field Park Company was lost at sea, including its vital equipment. After the landings, the engineering work required was considerable, while the arrival of engineer units was slow and they were widely scattered. In December 1942, a month after the first landing, the Commanding Royal Engineer (CRE) of 1st ATRE, Lt-Col L.E.A. Gwynne, commanded the advanced engineering base at
Bône in Tunisia with 587th Field Company and other workshop and park units. Allied ports and bases suffered severely from enemy bombing, and the CRE spent several nights directing the rescue of personnel trapped in bombed buildings at Bône. Meanwhile, 586th Field Company was working in the
Philippeville, Algeria area, including preparing approach roads and cuttings for the 160-foot span
Bailey bridge erected at
Souk El Khemis. By February, the CRE was in charge of bridging and road improvements to allow transporters carrying the new heavy
Churchill tank to reach their concentration area at
El Kef. During the
Battle of Kasserine Pass, in February 1943, the right flank of the British
V Corps was uncovered, and formations were hastily improvised to fill the gap, including
Nickforce and
1st (Guards) Brigade. A composite RE force, including 561st and 587th Field Companies, was sent up, and over three nights laid an extensive minefield under fire from enemy tanks. To support
Eighth Army's attack on
Wadi Akarit on 6 April, First Army attacked towards
Kairouan to cut off the enemy retreat. The approach roads for
128th Infantry Brigade Group were little more than 150 miles of sand tracks, and had to be improved by 586th Field Company, assisted by
US engineers from
II Corps. On 8 April, 128th Bde captured Pichon in an operation requiring two crossings of the bed of the Oued Marguellil and considerable mine clearance. The Tunisian campaign ended on 12 May with the surrender of
Armeegruppe Afrika.
Italian campaign First Army was disbanded at the end of the campaign, and 1st ATRE was transferred to Eighth Army in July 1943 and redesignated
8th Army Troops RE (8th ATRE). After the Battle of the Sangro (19 November–3 December), the
River Sangro rose rapidly and swept away all the temporary bridges. 8th ATRE began urgent work on 4 December for a high-level Sangro Bridge on Highway 16, the site being floodlit at night. This, which was longest Bailey bridge built during the Italian campaign, was opened to traffic on 14 December. After the German
Winter Line had been breached in the summer of 1944, Eighth Army renewed its advance up Highway 16, with 561st and 586th Field Companies completing a Bailey bridge and a causeway across the River Cessano to prepare the jumping-off line for the assault crossing of the River
Metauro on 25 August, after which 586th and 587th Field Companies bridged the Metauro to continue the highway and the causeway while the army moved on to breach the
Gothic Line. In early 1945, 8th ATRE was part of a large engineer force, known as the Po Task Force, which was formed to prepare for the formidable crossing of the
River Po. On 9 and 11 April the
Senio and
Santerno were crossed as the army advanced into the
Po Valley, and in the days that followed, 8th ATRE built Bailey bridges across these rivers. The 360-foot Santerno bridge was jointly built with the South African Corps Troops Engineers,
SAEC, and was thus named the 'Springlish' bridge. On 19 April, 8th ATRE was called in to dam the Marina Canal and prevent flooding. In the final stages of the campaign, the Po and
Adige were rapidly crossed, and 8th ATRE remained behind to build a 400-foot high-level Bailey bridge over the Adige to maintain the army's communications. This was begun on 30 April and opened on 6 May, hostilities in Italy having ended on 2 May. 8th ATRE was disbanded in or after September 1945. ==Postwar==