On 23 April 1918 the British raided Zeebrugge and Ostend with the intention of blocking the entrances to the canals linking the German destroyer and U-boat base at Bruges to the sea. These bases had been bombarded a number of times since August 1915.
Vice Admiral Roger Keyes succeeded Vice Admiral Sir Reginald Bacon in command at Dover on 1 January 1918. Keyes had in his previous job as the Admiralty’s Director of Plans prepared a plan to block Ostend and Zeebrugge. Bacon had made several changes to the plan. Keyes dropped Bacon’s intention of destroying the lock gates as well as blocking the locks, as he thought that this was impracticable. He retained his predecessor’s idea of landing on the mole at Zeebrugge in order to capture guns that threatened the approach of the blockships and to provide a diversion. This meant that a battalion of marines was needed as well as sailors.
The old armoured cruiser HMS Vindictive (Captain Alfred Carpenter) would carry the first wave of the Zeebrugge assault force. Her armament, apart from two 6 inch guns on each side of the upper deck was removed and replaced with weapons more useful in an opposed landing: an 11 inch and two 7.5 inch howitzers; two flamethrowers; five pom-poms; 16 Lewis machine guns; and 16 Stokes mortars. The rest of the troops would be carried by two Mersey ferries, Iris (Commander V. Gibbs) and Daffodil (Lieutenant H. G. Campbell), which had double hulls and double bottoms, making them hard to sink, and had a shallow draft, enabling them to steam over minefields. However, it also meant that their decks were low, so they needed 30 foot scaling ladders to reach the parapet of the mole. The three assault ships were all fitted with grappling hooks to secure themselves to the mole.
Five old unarmoured cruisers were chosen to be the blockships: HMS Thetis (Commander R. S. Sneyd), Intrepid (Lieutenant S. S. Bonham-Carter) and Iphigenia for Zeebrugge; and HMS Sirius and Brilliant for Ostend. They carried minimal crews but kept some guns in order to fire as they approached and were fitted with extra steering positions to prevent a single hit disabling them. They were filled with cement to make it harder to move them and fitted with explosive charges to blow out their bottoms and sink them in the locks, with firing positions both fore and aft. Two C-class submarines, C1 (Lieutenant A. C. Newbold) and C3 (Lieutenant R. D. Sandford), were to destroy the viaduct that connected the Zeebrugge mole to the shore by exploding charges stowed in their bows.
The attack would be covered by a smoke screen. Existing phosphorus based ones made dense but also created flames that were a beacon at night. Keyes therefore got Wing Commander Frank Brock, a former Royal Naval Air Service officer now serving with the newly formed Royal Air Force, to devise a substitute. Brock, a member of the family that founded and then still owned Brock’s, a large fireworks company, used chlor-sulphonic acid to produce dense smoke without flames. It was also used in saxin, a synthetic substitute for sugar, and 82 tons were needed. There was only one British manufacturer, so tea drinkers who used sugar substitutes had to drink unsweetened tea in order to provide enough chlor-sulphonic acid.
The German coastal defences were formidable. There were also anti-aircraft batteries, including two guns on the mole. The numbers below are British estimates, which according to Mark Karau underestimate the actual numbers. However, the British estimate of 38 U-boats and 28 torpedo boats at Bruges and 30 destroyers at Zeebrugge was too high.
|Star shell howitzer||1|
|3.5 inch (88 mm)||4||2|
|4.1 inch (104 mm)||5||4||3|
|5.9 inch (150 mm)||15||7|
|6.7 inch (170 mm)||4|
|8.2 inch (208 mm)||4|
|11 inch (280 mm)||12||8|
|15 inch (380 mm)||4|
Source: Corbett, J. S., Newbolt, H., Naval Operations. 5 vols (London: HMSO, 1938), vo. v, pp.246-47.
A 580 yard long railway viaduct, just wide enough to carry the railway, connected the shore to the Zeebrugge mole. The mole curved to the north east. It was 1,850 yards long and 80 yards wide and made of masonry. There was a 16 foot tall parapet on the western (seaward) side. A narrow masonry extension 260 yards long ended with a lighthouse. The mole batteries were on the extension, with an unimpeded arc of fire on any vessels approaching. the anti-aircraft guns were in a wired position 150 yards from the end of the mole, with a trench running across the mole. The gun crews and the mole’s 1,000 man garrison were housed in reinforced concrete sheds. There was a seaplane base at the south west end of the mole, which had its own garrison and concrete sheds.
The British took advice from Belgian engineers, including two men who had recently escaped and had worked on a Zeebrugge dredger during the occupation, about the best places to position the block ships. The attack was to be preceded by aerial bombing and then an hour long bombardment of Ostend by seven monitors and Zeebrugge by two monitors. Similar attacks were made in the weeks before the operation to make this seem like a routine operations.
A total of 165 vessels, 82 officers and 1,698 marines and seamen took part in the operation. As well as the assault and block ships, the monitors and numerous smaller craft, 29 destroyers would participate, with seven light cruisers, two flotilla leaders and 14 destroyers of the Harwich Force covering in case German ships tried to intervene from the north east. It was not an entirely British operation, as the French contributed seven torpedo boats and four motor launches.
Keyes insisted that the men on the block ships and submarines should all be volunteers and unmarried. He said that the other participants were taking no greater risks than the infantry on the Western Front, but in practice the number of men keen to take part was far more than the number needed.
Keyes originally intended to command from HMS Vindictive, but then realised that he needed to be able to move around to ensure that the various parts of the operation were going well. He therefore transferred his flag to the destroyer HMS Warwick.
The force sailed on 11 April. While it was en route the RAF bombed Zeebrugge. At 00:45 am the expedition stopped in order to remove from the block ships the men needed for the passage but not the assault. Before it could get underway again the wind stopped and then began to blow from the wrong direction for the smoke screens. Keyes decided that it was impossible to attack without a smoke screen and called off the mission. Coastal Motor Boat 33 was captured by the Germans, who found plans on board that revealed that a blocking expedition at Ostend was planned.
Another attempt was made on 13 April, but it had to be called off because the wind was too strong. There would not be another period when there was sufficient darkness and high water for three weeks. The Admiralty was inclined to cancel the operation on the grounds that surprise had been lost and the men could not be kept cooped up for so long. Keyes, however, persuaded them to let him try again between 22 and 28 April, when the high water was suitable. However, there was a full moon on 26 April.
The assault troops had been accommodated on the pre-dreadnought battleship HMS Hindustan in port, but she was very crowded. Keyes arranged for HMS Dominion, another old battleship, to be sent in order to improve the living conditions ahead of the second attempt.
The weather forecast on 22 April was favourable, with strength and direction of the wind being suitable and a good chance of clouds to obscure the moon. The expedition therefore set sail that day, with the attack to take place in the early hours of 23 April: St George’s Day.
The aerial attack had to be cancelled because of rain, but the monitors started to bombard Ostend at 11:10 pm and Zeebrugge 20 minutes later. Coastal motor boats began to lay smoke screens at 11:30 pm and attacked the western end of the Zeebrugge mole in order to distract the Germans from the approaching Vindictive. Keyes had HMS Warwick positioned so that he could see both the attack on the mole and the approach of the block ships.
The Germans did not realise what was happening until the last minute, but then benefitted from a change in the wind. The smokescreen was blown across the approach routes, meaning that British vessels could not see each other, but the Germans could see them as they emerged from the smoke. Vindictive emerged just after midnight, coming under heavy fire. She suffered heavy casualties and many of her guns were put out of action. Captain H. C. Halahan, commander of the naval landing parties, Lieutenant-Colonel B. H. Elliot, commander of the Royal Marine landing parties and Major A. A. Cordner, his second in command, were all killed.
Vindictive, Iris and Daffodil managed to get alongside the mole, a considerable feat of seamanship. Anchoring was very difficult. The surviving landing parties managed to get onto the mole under heavy fire. They could not destroy the mole’s guns, but the attack on the mole succeeded as a diversion. The Germans saw the block ships entering the harbour but probably assumed that the attack on the mole was the first stage in a landing.
The towline of C1, one of the two submarines that were to be blown up against the rail viaduct connecting the mole to the shore, parted, meaning that only C3 reached the start line. Her crew were meant to abandon ship after setting her on a course for the viaduct, but her captain Sandford decided to ram the viaduct with the crew still on board and then light the fuses. They then took to a motor skiff that they had to row because of damage to its engine. They were just clear when the explosives blew up and destroyed 100 feet of the viaduct, including the telephone wires connecting the defenders of the mole to the German headquarters, They were then firing on HMS Thetis, the first of the block ships.
Thetis was badly damaged and then was fouled by nets that had been laid across the harbour. She was unable to proceed to her target lock gates and ran aground before detonating her explosive charges. She had, however, cleared the way for Intrepid and Iphegenia to reach their target, where they grounded and blew themselves up. Motor launches took off the crews of the block ships. The British then withdrew, but the destroyer HMS North Star was sunk by the battery at the head of the mole. The destroyer HMS Phoebe took most of her crew off. Vindictive, Iris and Daffodil managed to withdraw, covered by Keyes’s flagship Warwick.
The attempt to block Ostend failed, however. The shift in the wind had a more serious effect there. The Stroom Bank buoy had been moved a mile east of the position that the British expected it to be in. the block ship captains could not be sure of their positions because of the smoke blowing towards them. When they sighted the Stroom Bank buoy they did not realise that it had been moved, steered on a course based on it being in its previous position and sank their ships in the wrong place.
The British lost two motor launches and HMS North Star plus the block ships and submarines deliberately sacrificed. They reported 70 dead, 400 wounded and 45 missing. I counted 199 listed on naval-history.net as dying at Zeebrugge on 23 April and 16 of dying of wounds during the next week, but there are probably others who later died of wounds. Wikipedia, sourcing P. Kendall, The Zeebrugge Raid 1918: The Finest Feat of Arms (Brimscombe Port: Spellmount, 2009), says that British casualties were 227 dead and 356 wounded. The Germans claimed that 214 British were killed, 383 wounded and 19 captured, themselves losing Germans lost eight dead and 16 wounded. The German destroyers V69 and S53 were lightly damaged and S63 heavily damaged but remained seaworthy.
One of the German dead was Matrose [Seaman] Hermann Künne, who had previously killed a British officer, probably Brock, in a cutlass fight.
The success at Zeebrugge and failure at Ostend led Keyes to propose another attack on Ostend. This was approved, but the British could not be ready to carry it out until the next period of favourable tides, which began on 9 May.
The Zeebrugge canal was left unusable at low tide. Admiral Ludwig von Schröder, the local German commander, feared at first that it would also be blocked at high tide, but four relatively small German torpedo boats though it on the evening on 24 April, with a U-boat following the next day. The larger destroyers would have to use the Ostend canal. By 14 May salvage work allowed them to use the Zeebrugge canal at high tide and a wooden walkway allowing foot and bicycle traffic to and from the mole was completed on 8 June,
The raid was executed very gallantly but its main effect was to boost Allied morale at a time when their armies on the Western Front were retreating as a result of the German March Offensive. Flanders based U-boats had to travel round Scotland to reach the Atlantic because of the Dover Barrage, which the German attack of 14-15 February showed could be attacked by destroyers based in the Helgoland Bight without them having to go via Bruges. The Germans, however, chose not to repeat that successful operation. . Both sides were happy enough with the outcome of the Zeebrugge Raid to give their commander a high award: the oak leaves to the Pour le Merite, popularly known as the Blue Max, for von Schröder; and a knighthood for Keyes.
Eight men were awarded the VC: the citations. originally published in the London Gazette, are on naval-history.net. Four of the awards were made under Clause 13 of the Victoria Cross Warrant. It allows that in a case where a large number of members of a unit deserve the VC it should be awarded by ballot of their peers. In this case the officers and the other ranks of the crews of the assault ships and the naval landing parties and the officers and the other ranks of the marine landing parties each selected one of their number.
Six awards were announced in July 1918, all to survivors and including the four Clause 13 medals. The naval officers chose Carpenter and the naval other ranks Able Seaman Albert McKenzie. The marine officers voted for Captain Edward Bamford and the marine other ranks for Serjeant Norman Finch. The other two went to Sandford of C3 and Lieutenant Percy Dean, commanding Motor Launch 282, which picked up survivors of the block ship,
Barrie Pitt’s book Zeebrugge: Eleven VCs before Breakfast also covers the 10 May attack on Ostend, in which another three VCs were awarded. It will be the subject of a later post.
 Naval Staff Monograph (Historical) 1922 vol. vi, The Dover Patrol i, pp. 25-50.
 J. S. Corbett, H. Newbolt, Naval Operations, 5 vols (London: HMSO, 1938). vol. v, -pp. 242-44.
 Ibid., p. 245; M. D. Karau, The Naval Flank of the Western Front: The German Marinekorps Flandern, 1914-1918 (Barnsley: Seaforth, 2003), p. 190.
 Corbett, Newbolt, Naval. vol. v, pp. 245-46.
 Karau, Naval, pp. 187-88.
 Corbett, Newbolt, Naval. vol. v, p. 247.
 Ibid., p. 249.
 Ibid., pp. 249-50.
 B. Pitt, Zeebrugge: Eleven Vcs before Breakfast (London: Cassell Military, 2003), p. 60.
 Ibid., p. 69.
 Corbett, Newbolt, Naval. vol. v. pp. 251-52.
 Pitt, Zeebrugge, p. 82.-81
 Corbett, Newbolt, Naval. vol. v. pp. 252-53.
 Ibid., pp. 254-55.
 Ibid., p. 256.
 Ibid., pp. 256-60.
 Ibid., pp. 260-61.
 Ibid., pp. 261-64.
 Karau, Naval, p. 196.
 Ibid., p. 198.
 Ibid., pp. 200-3.