By 1918, the British Grand Fleet had successfully contained the German High Seas Fleet, with little chance of it emerging from the North Sea ports, since the inconclusive Battle of Jutland in 1915. However, as was to be the case in the Second World War, the German submarine threat was extremely dangerous to Allied shipping - so much so that the British Isles experienced severe food shortages in 1917. Although the convoy system had vastly improved the situation, there was still a large threat from German vessels operating from Bruges, in north Belgium, especially to supply ships supporting allied troops in northern France.
To combat this, the commander of the Dover Patrol, Vice Admiral Keyes, devised a plan to disable the ports of Ostend and Zeebrugge, the outlets of enemy ships into the North Sea from their base eight miles inland. Each was connected to Bruges by a canal, both fitted with locks to allow access to the ships at any stage of the tide. The towns had been captured by the Germans during their advance and the "race to the sea" in 1914, and had been used as submarine staging points ever since. It is estimated that around 18 submarines and 25 destroyers were based at Bruges.
There were early versions of the submarine pens used in World War Two built by the Germans at Ostend and Zeebrugge, and these were impenetrable to any contemporary bombs, as air warfare was still in its infancy at this time. Therefore an assault from the sea was the only option - and Keyes intended to block the vital canals to deny the enemy access to the precious allied North Sea shipping.
To accomplish the task of blocking the canals at Zeebrugge and Ostend, the plan was to sink blockships at the entrances to the canal locks. All other objectives, such as causing as much damage to the Mole (a concrete jetty, a mile and a half long, eighty yards across at the widest point and stationed with gun batteries to protect the harbour entrance, and connected to the shore by a fairly flimsy wooden viaduct) at Zeebrugge, were subsidiary to this.
The mole would be attacked first, to detract attention from the blockships moving towards the mouth of the canal. It was also planned that raiding troops would destroy the guns on the seaward side of the mole, in order to prevent them firing on the blockships. Two old submarines were also to be towed into the viaduct, packed with explosives. The destruction of this would prevent a German counterattack from the landward side, it was hoped. The ships designated for scuttling in the mouth of the lock were the old minelayers HMS Intrepid, HMS Iphigenia and HMS Thetis.
The major problem with this plan was its complexity. Hugely ambitious, there was extremely little margin for error in the scheme. Also, as there would be a mixture of seamen and marines in the assault groups, there was a large potential for serious command and control confusion. There was also a worrying emphasis on attacking with the bayonet only, as the Western Front had highlighted the need for fire and maneouvre using grenade and Lewis gun (relevant in fighting amongst buildings on the mole). Very few officers in 4th RM had recent experience in fighting on the front, however.
The men chosen to undertake this daring raid were those of the 4th Battalion Royal Marines (4th RM). Although the marines were not dedicated Commando forces until the Second World War, one of the roles of these "soldiers and sailors too" was to provide parties for such assaults. The main role of the marines at this time remained to serve in capital ships (i.e. battleships) manning the guns, however. Although the 4th battalion had been raised to assist with the situation in Northern Ireland following the Easter Rising of 1916, it never served there. Instead it was used to provide reinforcements for RMLI ("Royal Marines Light Infantry", as opposed to "Royal Marines Artillery" or RMA, until the amalgamation of the two in 1923) battalions fighting on the Western Front. This practice was ended in early 1918, and the 4th was quickly brought up to full strength. During the training for the Zeebrugge raid, the Adjudant General of the marines visited and made it clear that any man could pull out if he wished to do so. Not one marine accepted the offer - the entire battalion were volunteers.
The 4th was reorganised especially for the assault, for example having three rifle companies instead of the usual four. The numbers were made up with a machine-gun section and a trench mortar section, both unseen in regular formations. Security was extremely tight during the training for the operation - King George V himself was unaware of the plan when he inspected the battalion at Deal on the 7th of March. The area to be attacked was recreated in England (at the Deal ranges), marked out with tape after using air photographs as reference, and even the men invloved were not told of the true nature of the raid (they were told that they were to join the 63rd Division in an attack on an enemy ammo dump somewhere in France). Each man carried 60 rounds of ammunition (remember, this is 1918: they were using bolt action rifles) and two grenades, and wore steel helmet, webbing equipment, bayonet, gas mask and swimming "belt" (like a life jacket). They also wore rubber-soled gym shoes to reduce noise. 4th RM numbered 30 Officers and 711 Other Ranks upon embarkation.
The raiding parties were to be embarked on three specially-adapted ships: HMS Vindictive (an old cruiser), HMS Iris and HMS Daffodil (both ferry boats from the Mersey river). Vindictive and Iris were to carry the main parties; Daffodil was to carry engineers, responsible for the demolition of buildings on the mole. The modifications to these vessels included extra armour plating to cover the exposed troops, strengthened foretops to allow more gun platforms to fire in support, and fitted gangplanks for disembaking the marines at the other end of the voyage across the channel. Once on board the ships but before the passage began, each platoon was briefed in detail on the objective, using models and photographs taken for the air. This was the first occasion that the men had been informed so - all in order to maintain the secrecy of the operation. However, the right combination of weather, wind and tide was critical, and due to the precise nature of this it was only found on five nights every two weeks. The raid was therefore postponed three times, twice after sailing, and as no man could go ashore (again for security reasons) the force remained embarked for sixteen days: until, on the 22nd of April, 1918, the order was given for the go-ahead.
The ships sailed across the channel with lights extinguished and an eerie silence amongst the waiting seamen and marines. With nerves stretched to breaking point, the men waited as destroyers and smaller craft pulled ahead of the lead ship (Vindictive) to lay a smoke screen. An air attack also succeeded in forcing the German gun crews on the mole into their shelters. As the troop carriers approached the mole and this bombing ceased, however, the wind shifted and blew the smoke away from the area, revealing the position of the British vessels.
Almost immediately a star shell burst above the ships, illuminating the exposed assault teams as they waited to pull alongside the mole. The silence was broken by the burst of shells landing in amongst the men, who were packed onto the decks. The ships were also illuminated with searchlights from the shore. Although still 250 yards from the landing area, Vindictive opened fire from her foretop, the signal for all guns on the British side to start firing. As the ships continued to close on the mole, more guns were ordered to cover the raiding parties as they prepared to disembark (although entire crews of some pieces were killed or too badly wounded to continue firing). Although the foretop was hit by a shell (killing or wounding every man) from the other side of the mole - it could be seen over the top - , a certain Sergeant Finch (RMA) kept his gun firing throughout the battle, despite his wounds.
At this point, however, things began to go seriously wrong. Both the CO and his second-in-command were killed by the same shell as they conferred on the bridge (despite a warning to keep their heads down from 4th RM's adjudant). Soon after, as command was transferred to the next ranking officer (the Major commanding C Company), at five past midnight, the first elements of the battered force began their assault upon the mole, using the only two of the fourteen ramps to have survived the shelling. B Company was the first onto the platform, and was quickly taken into action against a squad of German riflemen by the Officer Commanding, a Captain Bamford. However, casualties on board had been so high that for several companies only a dozen or so of the 45 original members actually landed. One of the submarines (designated "C-3") managed to destroy the viaduct at this time also, cutting off any potential reinforcements from reaching the fight on the mole; the other submarine did not arrive at all.
The second wave of men now began to put ashore. However, due to necessity Vindictive had berthed alongside the mole at a rather different position than planned (300 yards too far) and, coupled with the high casualty rate, this forced a rapid change of plan. The adjudant, a Captain Chater, and Bamford (whose "totally unperturbed manner" had "the most reassuring effect on all who came in contact with him that night") discussed the next action to be taken. As the primary objective of the diversionary assault on the mole was to attack the fortified landward end, it was decided that this was what was to be done. Having been ashore for only 45 of the planned 85 minutes, it was expected that enough time remained to do so.
However, as Bamford led three of his platoons across open ground towards the German positions when the ship's siren was heard. This was taken to be the emergency recall signal, and the order for withdrawal was given. It was not, in fact, the correct signal, but Chater sought confirmation from the captain of the Vindictive on his return to the ship. It became apparent that a withdrawal was desired, so Chater went back to the mole in order to pass the message to any troops within earshot. Most made it back to the ship, but others (3 NCOs and 10 privates, to be precise), due to the confusion caused by the incorrect signal, remained behind and were later captured as prisoners of war. The Vindictive left the mole at around 1250 am.
The Iris, on the other hand, failed to land a single man on continental territory. Although she did pull up alongside the mole ahead of Vindictive, the grappling irons could not be attached; several naval officers were killed in the attempt. Constantly under fire, Iris eventually tried to pull up alongside Vindictive to put men ashore across the larger vessel, but the recall was sounded before this could be accomplished. The heavy bombardment took its toll: one group of 56 men lost 49 dead and the rest wounded to a single shell. Iris lost 8 officers and 69 men dead, with 105 all ranks wounded, of her embarked men that night. The withdrawal of both the Iris and the Vindictive was successfully covered by smoke, and no more casualties were sustained as they limped back across the channel to Dover.
The officers and men of 4th RM, plus the seamen who had taken part, all felt that the operation was a dismal failure; after all, not one of their objectives had been achieved. However, Admiral Keyes himself was there to greet the battalion (what was left of it) was they came off the ships at 8 am, and expressed his feeling that it had in fact been a great success. He explained that an aeroplane had been over Zeebrugge that morning, and that the canal had been blocked as planned. The officers, on the other hand, told the admiral their own view of the affair - although the carnage and wreckage aboard the ships spoke for itself. The 4th took the train back to the Deal depot almost immediately, and the task of reorganisation began. 4th RM began with around seven hundred and thirty men, but sustained three hundred and sixty-six casualties during the raid on Zeebrugge (including 10 dead officers; this number also including both the CO and the 2i/c).
It was decide that the battalion would receive a Victoria Cross for its part in the operation; who was to recieve it would be decided by ballot. Keyes was to present the elected man with the award at Deal, but when he arrived it was revelard that, in fact, two awards were to be made. Captain Bamford received the most votes; Sergeant Finch second. As two VCs were to be given, it was decided by the CO and the adjudant that Finch logically deserved the second award. In addition to these awards, five VCs were presented to mebers of the Royal Navy for their actions at Zeebrugge. Lastly, for a reason best known to the Admiralty, it was decided that no battalion was to be numbered the 4th from that point on - and thus no battalion could claim the proud history that went with it.
Although a plane had indeed seen the blockships in the mouth of the canal, they had not actually succeeded in blocking access. Thetis had ran aground just short, and Iphigenia accidentally rammed Intrepid, pushing the latter off the correct position. The canal was therefore not sealed, despite the scuttling of both. The Germans succeeded in creating a route around the sunken ships for their U-boats within two days. Attempts to block the Ostend canal, the diversions not involving marines, also failed.
Despite this, the courage of the participating personnel of both the Royal Marines and the Royal Navy remains undiminished. The operation also reduced the German confidence in the belief that their submarine bases were impregnable, and also importantly restored positive public opinion in the British navy, after years of seeming inactivity and the unimpressive Battle of Jutland. The war on the Western Front was also going badly at this time; the Raid on Zeebrugge provided a much needed boost to morale as the Germans risked everything in a last-ditch, all-out attack. Zeebrugge also demonstated the usefulness of marines as amphibious raiding troops - something Winston Churchill, as the head of the Admiralty, would take note of and implement in times of need.
Major General (retd.) Thompson, Julian: "The Royal Marines: from sea soldiers to a special force" (2000)
A diagram of the operation can be seen at: