In March 1918, it suffered extremely heavy losses during Operation Michael the German spring offensive and was withdrawn from the line and reduced to a cadre to be rebuilt.

One of the three companies of Royal Engineers, was sent to France in 1915 to join the 48th (South Midland) Division and during 1916, three of the four heavy and howitzer artillery batteries were withdrawn or broken up.

[10] On 12 April, Brigadier-General Godfrey Matthews, a former Royal Marine officer commanding 198th Brigade, was wounded by shellfire and died the next day.

[11] In June, the division was transferred to the XV Corps of the Fourth Army on the relatively quiet coastal sector in Flanders.

[16] At zero hour, the 198th Brigade attacked on the left flank of the divisional front, into defences which had been little damaged by the artillery bombardment, advancing behind a meagre creeping barrage and were held up 300 yards (270 m) short of the first objective.

A German counter-attack was repulsed at 5:10 p.m. and before nightfall, the divisional commander ordered a short withdrawal, to link with the 49th Division on the left and to avoid enfilade fire from the Bellevue Spur.

[3] This was a change made in all British divisions, to bring the remaining battalions in France up to strength and to increase the ratio of artillery to infantry.

[24] Under a new defence in depth scheme, small strongpoints in a "forward zone" was to delay and disrupt an attack, harassing it with machine-gun fire.

The British were used to deliberate attacks in trench warfare conditions, not the rapid counter-attacks on the defensive that the German army had perfected since early 1915 and felt vulnerable in what they saw as exposed positions.

On the right flank, near the boundary with 24th Division, a reserve company of 2/7th Manchesters held a defensive position from 11:00 am to 7:00 pm, when they surrendered, having lost 70 per cent casualties and run out of ammunition.

The northern element of the division's defensive plan was a fortified quarry outside the village of Templeux-le-Guérard, held by the 2/7th Lancashire Fusiliers and 1/5th Border Regiment but this had been quickly surrounded and bypassed by the attackers, to be mopped up later in the day, with only a few men escaping.

On 24 March, the German army crossed the Somme and the 2/8th Lancashire Fusiliers counter-attacked the bridgeheads without success but continued to hold a line close to the river.

[31] Expecting a follow-up attack the next day, 149th Brigade was temporarily attached to 66th Division and both units were slowly pushed back from the banks of the Somme, withdrawing to Assevillers as night fell on 25 March.

"Little's Composite Battalion" with the remaining troops of the 198th Brigade, moved from reserve to Foucaucourt and defended the village until the early afternoon, retired to Framercourt and then filled a 3,000-yard (2,700 m) gap between the 66th and 39th divisions.

[46] On 29 March, near Vauchelles-lès-Domart, Malcolm had been badly wounded in his good leg (he was lame in the other, following an injury in South Africa) and left the division to recover, command being taken temporarily by Brigadier-General A. J.

[48][49] At 35, Bethell became the youngest man to command a division during the war; while a temporary Major-General, he still held the substantive rank of captain.

[50] A driven and mercurial figure, Bethell inspired both admiration and loathing from his contemporaries, who saw him as an outstanding commander but with a furious and often unjustified, temper.

[53] Following its losses, the 66th Division was reduced to cadre early in May; which meant that infantry battalions were cut to ten officers and about 45 men, the surplus being sent to base depots; the artillery, engineer and machine-gun units were distributed among other formations.

[55][56] During the summer, Bethell continued planning for the rebuilding of the division, having recruited a staff he felt he could work with, expecting that experienced men would become available as drafts returned from the Mediterranean.

Overseas divisions there had suffered fewer casualties and the reduction from four to three battalions per brigade meant that large numbers of men would be returning.

[58] The training process was complicated by a rigid schedule laid down by the American high command, who strongly objected to any deviation from their plans.

About thirty infantry battalions were attached for short periods and the divisional artillery and supply columns remained in support of the front line, while one ambulance company was later transferred to serve with the American 27th Division.

The division attacked at dawn on 8 October, in the opening phase of the Second Battle of Cambrai and captured the village of Serain by nightfall against determined resistance.

After this breakthrough, the division moved forward 14 miles (23 km) in three days, with patrols of the Connaught Rangers entering the outskirts of Le Cateau on 10 October.

[63][64][65] On the night of 16 October, the divisional pioneers and engineers bridged the Selle and the South African Brigade crossed in thick fog to capture Le Cateau, in a costly attack.