Part of the Western Front in World War I
The Battle of Messines (7–14 June 1917) was an attack by the British Second Army (General Sir Herbert Plumer), on the Western Front, near the village of Messines (now Mesen) in West Flanders, Belgium, during the First World War. The Nivelle Offensive in April and May had failed to achieve its more grandiose aims, had led to the demoralisation of French troops and confounded the Anglo-French strategy for 1917. The attack forced the Germans to move reserves to Flanders from the Arras and Aisne fronts, relieving pressure on the French.
The British tactical objective was to capture the German defences on the ridge, which ran from Ploegsteert Wood (Plugstreet to the British) in the south, through Messines and Wytschaete to Mt Sorrel, depriving the German 4th Army of the high ground. The ridge gave commanding views of the British defences and back areas of Ypres to the north, from which the British intended to conduct the Northern Operation, an advance to Passchendaele Ridge and then the capture of the Belgian coast up to the Dutch frontier. The Second Army had five corps, three for the attack and two on the northern flank not part of the operation; XIV Corps was in General Headquarters reserve. The 4th Army divisions of Group Wytschaete (, the IX Reserve Corps headquarters) held the ridge and were later reinforced by a division from Group Ypres ().
The British attacked with the II Anzac Corps (3rd Australian Division, New Zealand Division and the 25th Division, with the 4th Australian Division in reserve), IX Corps (36th (Ulster), 16th (Irish) and 19th (Western) divisions and the 11th (Northern) Division in reserve) and X Corps (41st, 47th (1/2nd London) and 23rd Divisions with the 24th Division in reserve). XIV Corps was in reserve, with the Guards Division, 1st Division, 8th Division and the 32nd Division. The 30th, 55th (West Lancashire), 39th and 38th (Welsh) divisions, in II Corps and VIII Corps, guarded the northern flank and made probing attacks on 8 June. held the ridge with the 204th, 35th, 2nd, 3rd Bavarian (relieving the 40th Division when the British attack began) and 4th Bavarian divisions, with the 7th Division and 1st Guard Reserve Division as (counter-attack) divisions. The 24th Saxon Division, relieved on 5 June, was rushed back when the attack began and the 11th Division, in reserve, arrived on 8 June.
The battle began with the detonation of nineteen mines beneath the German front position, which devastated it and left large craters. A creeping barrage, deep, began and protected the British troops as they secured the ridge with support from tanks, cavalry patrols and aircraft. The effect of the British mines, barrages and bombardments was improved by advances in artillery survey, flash spotting and centralised control of artillery from the Second Army headquarters. British attacks from 8 to 14 June advanced the front line beyond the former German (Chord Position, the Oosttaverne Line to the British). The battle was a prelude to the much larger Third Battle of Ypres, the preliminary bombardment for which began on 11 July 1917.
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Background.
British strategy 1916–1917.
In 1916, the British planned to clear the Germans from the Belgian coast to deny them the use of the ports as naval bases. In January, Plumer recommended to Field Marshal Sir Douglas Haig the capture of Messines Ridge (part of the southern arc of the Ypres Salient) before an operation to capture the Gheluvelt plateau further north. The highest ground north of the Messines–Wytschaete ridge lies on the Menin road, between Hooge and Veldhoek, from Gheluvelt, at the west end of the main Ypres ridge, which runs from Ypres, east to Broodseinde and then north-east to Passchendaele, Westroosebeek and Staden. The British called it the Gheluvelt Plateau or Menin Ridge. Roads and tracks converged on the Menin road at this point (Clapham Junction to the British). The east end of the Gheluvelt plateau was on the west side of Polygon Wood. A flat spur either side of the Menin road ran about south-eastwards towards Kruiseecke and was about wide at Veldhoek, with a depression on the west side through which the Bassevillebeek flowed southwards and another on the east side, through which the Reutelbeek also flowed south. The spur widened to almost between Veldhoek and Gheluvelt.
A Flanders campaign was postponed because of the Battle of Verdun in 1916 and the demands of the Battle of the Somme. When it became apparent that the Second Battle of the Aisne (the main part of the Nivelle Offensive, 16 April to 9 May 1917) had failed to achieve its most ambitious objectives, Haig instructed the Second Army to capture the Messines–Wytschaete Ridge as soon as possible. British operations in Flanders would relieve pressure on the French Armies on the Aisne, where demoralisation amid the failure of the Nivelle Offensive had led to mutinies. The capture of Messines Ridge would give the British control of the tactically important ground on the southern flank of the Ypres Salient, shorten the front line and deprive the Germans of observation over British positions further north. The British would gain observation of the southern slope of Menin Ridge at the west end of the Gheluvelt plateau, ready for the Northern Operation.
Ypres salient.
Ypres is overlooked by Kemmel Hill in the south-west and from the east by a line of low hills running south-west to north-east. Wytschaete (Wijtschate) and Hill 60 are to the east of Verbrandenmolen, Hooge, Polygon Wood and Passchendaele (Passendale). The high point of the ridge is at Wytschaete, from Ypres, while at Hollebeke the ridge is distant and recedes to at Polygon Wood. Wytschaete is about above the plain; on the Ypres–Menin road at Hooge, the elevation is about and at Passchendaele. The rises are slight, apart from the vicinity of Zonnebeke, which has a gradient of 1:33. From Hooge and further east, the slope is 1:60 and near Hollebeke, it is 1:75; the heights are subtle and resemble a saucer lip around the city. The main ridge has spurs sloping east and one is particularly noticeable at Wytschaete, which runs south-east to Messines (Mesen) with a gentle slope on the east side and a 1:10 decline westwards. Further south, is the muddy valley of the River Douve, Ploegsteert Wood (Plugstreet to the British) and Hill 63. West of Messines Ridge is the parallel Wulverghem (Spanbroekmolen) Spur and on the east side, the Oosttaverne Spur, which is also parallel to the main ridge. The general aspect south and east of Ypres, is one of low ridges and dips, gradually flattening northwards beyond Passchendaele, into a featureless plain.
Possession of the higher ground to the south and east of Ypres, gives an army ample scope for ground observation, enfilade fire and converging artillery bombardments. An occupier also has the advantage that artillery deployments and the movement of reinforcements, supplies and stores can be screened from view. The ridge had woods from Wytschaete to Zonnebeke giving good cover, some being of notable size, like Polygon Wood and those later named Battle Wood, Shrewsbury Forest and Sanctuary Wood. In 1914, the woods usually had undergrowth but by 1917, artillery bombardments had reduced the woods to tree stumps, shattered tree trunks tangled with barbed wire and more wire festooning the ground, which was full of shell-holes; fields in the gaps between the woods were wide and devoid of cover. The main road to Ypres from Poperinge to Vlamertinge is in a defile, easily observed from the ridge. Roads in the area were unpaved, except for the main ones from Ypres, with occasional villages and houses dotted along them. The lowland west of the ridge was a mixture of meadows and fields, with high hedgerows dotted with trees, cut by streams and a network of drainage ditches emptying into canals.
Topography.
In Flanders, sands, gravels and marls predominate, covered by silts in places. The coastal strip is sandy but a short way into the hinterland, the ground rises towards the Vale of Ypres, which before 1914 was a flourishing market garden. Ypres is above sea level; Bixschoote to the north is at . To the east the land is at for several miles, with the Steenbeek river at near St Julien. There is a low ridge from Messines, at its highest point, running north-east past Clapham Junction at the west end of Gheluvelt plateau ( ;templatestyles src="Fraction/styles.css" / ;2+1⁄2 miles from Ypres at and Gheluvelt, above to Passchendaele, ( ;templatestyles src="Fraction/styles.css" / ;5+1⁄2 miles from Ypres at declining from there to a plain further north. Gradients vary from negligible, to 1:60 at Hooge and 1:33 at Zonnebeke. Underneath the soil is London clay, sand and silt; according to the Commonwealth War Graves Commission categories of "sand", "sandy soils" and "well-balanced soils", Messines ridge is well-balanced soil and the ground around Ypres is sandy soil. The ground is drained by many streams, canals and ditches, which need regular maintenance. Since the First Battle of Ypres in 1914, much of the drainage had been destroyed, though some parts were restored by land drainage companies from England. The area was considered by the British to be drier than Loos, Givenchy-lès-la-Bassée (Givenchy) and Plugstreet (Ploegsteert) Wood further south.
Prelude.
British preparations.
The Second Army centralised its artillery and devised a plan of great sophistication, following the precedent set at the Battle of Arras in April. The use of field survey, gun calibration, weather data and a new and highly accurate 1:10,000 scale map, much improved artillery accuracy. Systematic target-finding was established by the use of new sound-ranging equipment, better organisation of flash-spotting and the communication of results through the Army Report Centre at Locre Château. Counter-battery artillery bombardments increased from twelve in the week ending 19 April, to 438 in the last ten days before the attack. A survey of captured ground after the battle found that 90 per cent of the German artillery positions had been plotted. The 2nd Field Survey Company also assisted mining companies by establishing the positions of objectives within the German lines, using intersection and a special series of aerial photographs. The company surveyed advanced artillery positions for guns to be moved forward to them and open fire as soon as they arrived.
The British had begun a mining offensive against the (Wytschaete position) in 1916. Sub-surface conditions were especially complex and separate ground water tables made mining difficult. Two military geologists assisted the miners from March 1916, including Edgeworth David, who planned the system of mines. Sappers dug the tunnels into a layer of blue clay underground, then drifted galleries for to points deep underneath the front position of , despite German counter-mining. German tunnellers came close to several British mine chambers, found the mine at La Petite Douve Farm and wrecked the chamber with a . The British diverted the attention of German miners from their deepest galleries by making many secondary attacks in the upper levels. Co-ordinated by tunnelling companies of the Royal Engineers, Canadian, Australian, New Zealand and British miners laid 26 mines with of ammonal explosive.
Two mines were laid at Hill 60 on the northern flank, one at St Eloi, three at Hollandscheschuur, two at Petit Bois, one each at Maedelstede Farm, Peckham House and Spanbroekmolen, four at Kruisstraat, one at Ontario Farm and two each at trenches 127 and 122 on the southern flank. One of the largest of the mines was at Spanbroekmolen; Lone Tree Crater formed by the blast of of ammonal in a chamber at the end of a gallery long, below ground was in diameter and deep. The British knew of the importance the Germans placed on holding the salient, after a captured corps order from stating "that the salient be held at all costs" was received by Haig on 1 June. In the week before the attack, 2,230 guns and howitzers bombarded the German trenches, cut wire, destroyed strongpoints and conducted counter-battery fire against 630 German artillery pieces, using 3,561,530 shells. The 4th Army artillery consisted of 236 field guns, 108 field howitzers, fifty-four 100–130 mm guns, twenty-four 150 mm guns, 174 medium howitzers, 40 heavy howitzers and four heavy 210 mm and 240 mm guns.
In May, the 4th Australian Division, 11th (Northern) Division and the 24th Division were transferred from Arras as reserve divisions for the Second Army corps in