VII Corps dispositions The front line of the 4th Division was held by the 12th Brigade on the left, between Albert and Dernancourt, and the 13th Brigade on the right, between Dernancourt and Buire-sur-l'Ancre. The forward positions of the salient held by the 4th Division were along the railway line, which ran along a series of embankments and cuttings, including a railway bridge immediately northwest of Dernancourt where the Dernancourt–
Laviéville road passed under the railway. A mushroom-shaped feature known as the Laviéville Heights overlooked the railway line, which curved around its foot. The foot of feature consisted of a number of gentle spurs and re-entrants, which hindered observation along the front line in both directions. This was difficult ground to defend, particularly where the railway line curved and skirted the northwestern corner of Dernancourt, as if the line there was overrun, the enemy would be able to fire into the rear of the troops lined out along the railway in both directions. Despite this, the Australian commanders considered it important to hold the railway line since, if it was not garrisoned, the enemy could assemble in the dead ground behind the embankment. A further difficulty arose from the fact that if an attack occurred during daylight, it would be almost impossible to move troops down the exposed slopes to reinforce the railway line without crippling losses, and troops withdrawing from the railway line would be similarly exposed. To afford them some protection along the railway line, the forward posts dug one-man niches in the near side of the embankment, but the only way for them to fire was to climb up and lie on top of the embankment, thus exposing themselves to enemy fire. To mitigate this problem, parties of the
4th Pioneer Battalion had been tasked to tunnel through the embankment, then dig out small T-shaped trenches on the far side. This work was still ongoing on the night of 4/5 April. After a rotation conducted on the night of 3/4 April, the 12th Brigade front line consisted of widely spaced
platoon posts, garrisoned by the
48th Battalion on the left and the
47th Battalion on the right, largely as they had been for the First Battle of Dernancourt. In the 13th Brigade area, the
52nd Battalion held the front line. On the left flank of the 4th Division were British troops of the 7th (Service) Battalion of the
Suffolk Regiment, which was part of the
35th Brigade,
12th (Eastern) Division,
V Corps. On the 4th Division's right flank, in the village of Buire-sur-l'Ancre itself, was a
company of the
3rd Pioneer Battalion, belonging to the 3rd Division, which was holding the front line west of Buire-sur-l'Ancre. On 4 April, as a result of consolidation of the forward positions of the division, MacLagan ordered that the main line of resistance was to be the railway line rather than the positions half-way up the hill. In doing so, MacLagan was concerned that the 12th (Eastern) Division on his left might be driven in, and specified that if this occurred, his forward commanders could withdraw to the former main line up the hill to the rear. This order had a significant impact on the coming battle, as it is doubtful that this order was received by the 52nd Battalion. Throughout that day, the troops of the 4th Division could hear the artillery fire associated with the renewal of the German offensive further south. Late that afternoon, a
prisoner-of-war captured by the 3rd Division stated that an attack was pending north of the Somme, and the troops that would be mounting it were already assembled. In the
Official History,
Charles Bean noted that the Australian troops were in "bouncing spirits", despite the rain of the previous few days.
12th Brigade The left flank of the 48th Battalion had been extended about further north than the sector it had held during First Dernancourt, taking up ground previously held by the 12th (Eastern) Division, including responsibility for the Albert–Amiens road. The battalion frontage now measured . The commanding officer of the 48th Battalion,
Lieutenant Colonel Raymond Leane, usually highly reticent to crowd forward areas with troops, requested and was granted authority from Gellibrand to hold his front line with three companies. This reflected the reduced manpower available to him after the casualties incurred during First Dernancourt. As the railway line near Albert was not in friendly hands, one company of the 48th Battalion was deployed in posts on either side of a grassy ravine alongside the Albert–Amiens road, and two held the railway line running south towards Dernancourt. Leane's fourth company was kept in support positions in an entrenchment known as Pioneer Trench, which had been dug by the 4th Pioneer Battalion on the Laviéville Heights some to the rear of the front line on the railway. This company occupied a section of Pioneer Trench that stretched north of the Albert–Amiens road. Leane had been allocated a company of the
46th Battalion, which he held in reserve in trenches near his headquarters on the high ground alongside the Albert–Amiens road. The 47th Battalion held the railway line from the bend to just short of the railway bridge with two companies. The left forward company (B Company) was positioned behind the embankment, and the right forward company (A Company) held a cutting where the railway line turned southwest, as well as the steep railway embankment near the bridge. The two platoons on the left of A Company were positioned forward of the cutting, with the two platoons on the right deployed behind the embankment. Behind and slightly up the slope from the boundary between the two forward companies was an old
prisoner-of-war (POW) cage. The commanding officer of the 47th Battalion, Lieutenant Colonel
Alexander Imlay, held his two remaining companies in support, garrisoning an old and overgrown French "practice trench" located uphill from the railway line along the edge of a sunken road that circled the hillside, sometimes coinciding with the road itself. This was a poor entrenchment, being far too wide and lacking
traverses. On the right of this trench, where the Dernancourt–Laviéville road ran through it, a knuckle of the slope blocked its field of view towards the railway line. About forward of the right support company (C Company) and back from the railway embankment was a quarry alongside the Dernancourt–Laviéville road. D Company was the left support company. Imlay had been allocated a company of the
45th Battalion, which was held in reserve in that section of Pioneer Trench that stretched south of the Albert–Amiens road. His headquarters was co-located with Leane's. The balance of the 45th and 46th Battalions were held in a reserve line of posts northeast of Laviéville near Gellibrand's headquarters. Within the 12th Brigade forward area were deployed the
Vickers machine guns of the
24th Machine Gun Company. Half of their guns were grouped into two batteries, each of four guns. One battery was located in the quarry forward of the 47th Battalion support trench, and the other was distributed along a trench which was located about northeast of the quarry. Due to their exposed locations, the crews of these two batteries were ordered not to show themselves or mount the guns in firing positions during daylight. If the infantry fired the S.O.S. signal or fell back from the railway line, they were to mount the guns regardless. The artillery of the 4th Division was in support of the 12th Brigade, consisting of the 10th and 11th
Australian Field Artillery (AFA) Brigades, located in a valley northwest of Laviéville. The inter-brigade boundary ran along the Dernancourt–Laviéville road.
13th Brigade After it relieved the 35th Division, the 13th Brigade held its front line with the 52nd Battalion, with three companies holding the railway line between Dernancourt and Buire-sur-l'Ancre. Its left forward company, which held the railway bridge northwest of Dernancourt, had a
Lewis machine gun post thrust out on the far side of the bridge. The 52nd Battalion's fourth company was located in a valley north of Buire-sur-l'Ancre near battalion headquarters, but the 4th Pioneer Battalion had dug a series of support posts along the lower slope, about behind the railway line. These posts ran through an abandoned
casualty clearing station (CCS), but did not reach as far as the cemetery west of the Dernancourt–Laviéville road. Being on an exposed slope, these posts were unoccupied during the day, but the fourth company had orders to occupy them in case of attack. If this occurred, the commanding officer of the 52nd Battalion, Lieutenant Colonel
John Whitham, had been given a company of the
51st Battalion, which was to automatically replace the fourth company of the 52nd Battalion in the valley north of Buire-sur-l'Ancre as soon as it moved forward. In the 13th Brigade area was another unoccupied trench, located at the top of the slope, about to the right rear of the 47th Battalion's support line, which had been dug prior to First Dernancourt. Two pairs of Vickers guns of the 13th Machine Gun Company were deployed on the slope above the railway embankment, with a third pair in the area of the left forward company, and several others further west. Whitham had also been given the rest of the 51st Battalion to use as reinforcements if necessary. In the meantime, the balance of the 51st Battalion was deployed along a line running south of and parallel to the Albert–Amiens road, north and northwest of Buire-sur-l'Ancre. The remaining battalions of the 13th Brigade, the
49th and
50th Battalions, were held as the divisional reserve in a line well to the rear, west of the village of Bresle. The 13th Brigade had substantial British artillery support available, comprising the 95th
Royal Field Artillery (RFA) Brigade, belonging to the
21st Division, as well as the 65th and 150th RFA Brigades, which were Army-level assets. These artillery units were deployed on the eastern outskirts of Bresle.
German plan of attack The German attack against the 4th Division, known as
Unternehmen Sonnenschein (Operation Sunshine), was to be delivered by the XXIII Reserve Corps using three divisions. In the north, the
79th Reserve Division would assault the sector held by the 48th Battalion, as well as the neighbouring sector of the 12th (Eastern) Division. It was to attack with two
regiments, the 261st Reserve Infantry Regiment (RIR) assaulting where the Albert-Amiens road ran out of Albert with the objective of capturing that portion of Pioneer Trench that extended north of the Albert-Amiens road, and occupied by the supporting company of the 48th Battalion. The 262nd RIR was to attack the railway embankment further south, and the 263rd RIR was held in reserve. It was likely considered that the Australian defences along this sector would be overrun with "little difficulty", especially given that the main effort of the corps assault further south near Dernancourt would threaten the rear of this sector. The XXIII Reserve Corps main effort was with the 50th Reserve Division, which had also been the primary assault formation used during First Dernancourt. Despite significant casualties suffered during that battle, it had rested for much of the following week, and its morale remained high. It was to attack on both sides of Dernancourt. The most critical task of the division was allocated to the 230th RIR, which was to assemble in the cellars of Dernancourt then assault the sector near the railway bridge. Its II Battalion was to lead the assault on the embankment, pushing on to capture the 47th Battalion's support trench and the portion of Pioneer Trench south of the Albert-Amiens road that was occupied by the company of the 45th Battalion that had been allocated to the 47th Battalion. II/230th RIR was to be followed by III and I Battalions in that order. The 229th RIR was tasked to exploit the gains achieved by the 230th RIR. The 231st RIR was to assault immediately north of the cutting at the bend in the railway line, near the boundary between the forward companies of the 47th Battalion. Once these initial objectives had been achieved, the whole 50th Reserve Division was to wheel to the left as the 79th Reserve Division drew level with it north of the Albert-Amiens road, and with the
13th Division on its left flank, the corps would push on towards Amiens. The artillery supporting the 50th Reserve Division had been allocated 16,000
gas shells for the preliminary bombardment of the British and Australian artillery batteries, which was to be heaviest between 08:30 and 09:00. The 50th Reserve Division was reinforced by one storm company of the 3rd Jäger Battalion, equipped with four machine guns, two trench-mortars and two
field guns, with a further storm company of that battalion attached to 230th RIR for "certain enterprises" along the railway line. Between Dernancourt and Buire-sur-l'Ancre, the assault would be launched by the 13th Division, which would attack with all three regiments. On the right, the 15th Infantry Regiment (IR) was to attack the railway line held by the 52nd Battalion from the woods near
Ville-sur-Ancre. In the centre, the 55th IR was to assault the line held by the 10th Brigade of the 3rd Division, between
Treux and Marrett Wood. On the left, the 13th IR would also attack the 10th Brigade line south of Marrett Wood. ==Battle==