The Day British Soldiers Blew Up 10,000 German Troops

Britain’s Great War is remembered as a bloody slog, but not all the battles were huge defeats or bittersweet Pyrrhic victories.    

At 3:10 am on June 7, 100 years ago, a line of mines under the German lines were detonated, blasting vast pillars of fire up through the high ground held by the Germans.

What would become known as the 'Battle of Messines' had begun.

This powerful military spectacle was the consummation of more than 18 months planning and preparation.

The war on the Western Front began when the Imperial German Army swept through neutral Belgium and northern France in 1914, bypassing the fortifications the French had built to repel them further south.

The result was a war of frontiers, as the Germans, French, and then BEF (British Expeditionary Force) vied with each other for control of territory.

The German forces, stretched out on a second front in the east, chose to strategically withdraw and build solid trench lines on ridges overlooking the British and French allied armies.

The Allies had dug their trenches in the low ground as close to the Germans as they could get. 

This gave the German defenders a territorial advantage on top of the one already possessed by defensive forces. Attacking machine gun positions and well-entrenched soldiers with deadly accurate rifles was already difficult enough - doing so whilst they held the high ground was even more so.

But in the tunnelling war, the tables were turned: The Allies only had to dig in a straight line to put themselves directly underneath their enemy’s trenches, whereas the Germans had to dig down and across to intercept them.

Pioneer battalions, filled mostly with coal miners, set to work exploiting this advantage.

While the stubbornness of trench lines frustrated the infantry’s efforts to revert back to a war of movement on the ground above, this same continuity only helped the miners below. Static enemy trenches lent themselves well to being mined.

Trenches were sometimes ranged against each other in a more-or-less parallel formation, but in some parts of the line a bulge known as a salient was the norm.

Salients were double-edged swords because they pressed intrusively into and dominated the enemy’s line, but they were also open to attack from three sides.

It was this vulnerability of the Ypres salient, held by the BEF just to the north, which prompted the attack on Messines to the south.(Notice that in the map above, the British salient near Ypres is at the top of the picture whilst the German salient further south at Messines is in the bottom half of the picture).

The British were planning (and later executed) an offensive from the Ypres salient in late July 1917.

Whereas this offensive was less well-planned, executed, and dogged by bad weather and enemy resistance that ground it down, the preparatory battle at Messines earlier that year was a stunning success.

Messines was chosen both because of its adjacent position to the Ypres salient and because its elevated position meant that any German defenders left alive there could hamper the British advance further north.

But in the south, the pioneers in General Plummer’s Second Army were ready with their answer to this problem, summarised chillingly in the BBC’s 1964 series The Great War.

"And now, one of the war’s most deadly methods reached its climax: The underground war. The war of mines and tunnels groping beneath no-man’s-land towards the enemy lines, in which men dug, and crouched, and fought and blew each other to pieces."

One veteran said: “The essence of mining the clay area was silence and secrecy. We wore felt slippers, rubber-wheeled trollies, wooden rails, and we spoke in whispers. And when the German blew us we never answered back, we suffered casualties and said nothing. We tried not to give away where we were.”

But for all the hard slogging, the work paid off. 

The British were able to lay a million pounds of high explosive in 19 mine tunnels – and at 3:10 on June 7, they detonated it.

Another veteran recalled:

“Suddenly the whole earth heaved and up from the ground came what really looked more like two enormous Cyprus trees, the silhouettes of great dark cone-shaped lifts of earth up to three, four, five thousand feet.” 

The blasts were felt as far away as London.

One soldier recounted how the whole hillside rocked like a ship at sea under the mine blasts and artillery covering the British, Canadian, and ANZAC infantry who charged forward on the heels of the blasts, ready to overwhelm any German survivors.

For their part, so many enemy soldiers were killed or taken prisoner that the Germans simply listed 10,000 men as missing that day.

Plumer’s army had won a spectacular victory, the outlines of which are still etched on the battlefield – the huge craters still occupy the pot-marked farmland of Flanders, the largest of which is now a giant pond.

But not all the remnants of the battle were peaceful landforms – in 1955 one of the unexploded mines from the battle was set off by a lightning strike on the outskirts of a sleepy village.

Thankfully the only casualty was a cow, but French and Belgian farmers continue to turn up ordinance from the First World War to this day.

Messines Ridge and The Great War are still with us a century later.

Cover image from 'Messines 1917: The Zenith of Siege Warfare' by Alexander Turner © Osprey Publishing, part of Bloomsbury Publishing. For more military history, visit Osprey Publishing's website.