D-Day Decrypts

The Bletchley Park Trust holds a unique collection of almost 250 German naval Enigma messages from the time of the Normandy landings launched on D-Day, 6 June 1944. Having provided invaluable intelligence for the planning of the invasion, the Codebreakers also supported the operation as it unfolded. Messages were intercepted, deciphered and translated in as little as two-and-a-half hours. To mark the 75th anniversary of D-Day, on Thursday 6 June 2019, Bletchley Park live tweeted, in real time, messages intercepted on 6 June 1944. You can delve deeper into some of the messages sent on 6 June 1944 in the album below. Reading these messages today it is possible to follow the events of the day from the perspective of the German navy (Kriegsmarine), as initial confusion gave way to realisation of the scale and importance of the unfolding invasion…

This Collections uncovered album was first published on 5 June 2019.

The first message in the collection indicates German commanders’ first inkling of what was taking place, with a command ordering “immediate readiness”. The 2nd Security Division based in Boulogne was responsible for the light gunboats, minesweepers and patrol boats tasked with defending the Normandy coast. It is unclear what triggered this warning, but it is likely reports of increased naval activity and the first parachute landings had been received.

Message reads: To: all units of the Second Defence Division. Immediate readiness.

In order to sow confusion, 500 dummy paratroopers were dropped in places away from the real landing zones. The Germans were evidently little fooled, however, and after American paratroopers were captured, it was correctly reported that an airborne landing had taken place in the south-east of the Cotentin peninsula. It was still unclear whether the landing was a raid, part of a larger operation, or even a diversion from an attack happening elsewhere.

Message reads: Some of the parachutists reported were straw dummies.

At 04.55 nine German vessels left Le Havre, ordered to sweep the coastline for enemy craft. At around 05.40 they stumbled upon the Allied fleet and, immediately receiving heavy fire, quickly launched eighteen torpedoes. The salvo narrowly missed several key vessels, including the command ship HMS Largs; its only victim was the brand-new Norwegian destroyer HNoMS Svenner, which quickly split in two and sank. Shortly afterwards the battleship HMS Warspite achieved a direct hit on one of the German patrol boats. Here its commander, Viktor Rall, reports the loss of the vessel.

Message reads: MOST IMMEDIATE. Boat 1509 hit and sinking.

As well as sea vessels, the Kriegsmarine also controlled numerous coastal gun batteries. One of the most important, with three 210mm guns, was at Saint-Marcouf, near Utah Beach; its commander, Oberleutnant Zur See Walter Ohmsen, was one of the first to report sighting the invasion fleet. The battery engaged the Allied warships and succeeded in sinking the destroyer USS Corry (here mistakenly identified as a cruiser). However, fire from other ships quickly knocked out one gun.

Message reads: MOST IMMEDIATE. Enemy cruisers after fire from MARCOUF sank at 0720. Battery unserviceable, 1 gun sustained direct hit.

By mid-morning Allied troops had landed on all five main beaches and the fleet continued its bombardment of the coastal batteries; the German naval commanders were receiving news of the progress of the land fighting and the scale of the operation was becoming apparent. Vierville and Colleville were the villages behind Omaha Beach, one of the two beaches allocated to American forces, where a bloody battle was taking place. Just to the west, US Army Rangers had scaled the steep cliffs to reach the gun battery on the Pointe du Hoc. The area from Ravenoville to the Vire estuary was the location of the other American beach, codenamed Utah, which had been secured against little opposition early that morning.

Message reads: MOST IMMEDIATE. MARCOUF area under heavy artillery fire. Between VIRE and ORNE, principally at VIERVILLE and COLLEVILLE, enemy tanks on land. Steep coast near PONT DU HOE ascended with scaling ladders, fighting in progress. No news from area RAVENOVILLE to VIRE estuary.

An hour later word had been received from the radar installation at Arromanches that tanks were ashore; this was the landing of the British 50th Infantry Division on Gold Beach. By midday the base was reported to be surrounded, and Hennecke’s evening report would state “Fate of ARROMANCHES personnel uncertain”.

Message reads: MOST IMMEDIATE. ARROMANCHES reports: 5 tanks (‘PANZER’) have landed near ASNELLES. English artillery is firing inland (‘HINEIN’). There seems to be a fairly large landing near VER-SUR-MER, as large formations are partrolling there. Continuous air recce, severe bombing attacks. Over 200 units, including destroyers, have been sighted.

The Kriegsmarine was even involved with fighting some distance inland. The crossings over the river Orne and Caen Canal at Benouville, which controlled the left flank of the beachhead, were famously captured in a daring midnight glider landing; the canal bridge became known as Pegasus Bridge. In the late morning two German craft from Ouistreham approached the bridge, apparently unaware it was in enemy hands. One boat was hit by a shot from a PIAT anti-tank weapon and ran aground, where the crew were captured; the other retreated, sending this report on the encounter shortly afterwards.

Message reads: The BENOUVILLE bridge over the CAEN canal is in the hands of the British. Two gliders have landed. Am withdrawing after a brush with the enemy.

In the late afternoon Admiral Theodor Krancke, who commanded all Kriegsmarine forces in France, issued this situation report from his headquarters in Paris. The main landing areas had now been identified, and he considered the main danger as laying in the British and Canadian sector. However, the belief that the Omaha Beach landing had been “cleaned up” was incorrect; by this time American troops had overcome the defenders and were pushing inland.

Message reads: Evening situation: Only air landings in the area DEAUVILLE to the ORNE. Area has been cleared up. The focal part of the enemy landings is ORNE – PORT EN BESSIN, especially to eastwards of ARROMANCHES. The enemy is on both sides of the ORNE canal as far as to northwards of BLAINVILLE. Powerful countermeasures are in progress. Air and sea landings between PORT EN BESSIN and VIRE have been cleaned up except for a pocket of resistance at ST. PIERRE. Between ST. VAAST and ((VIRE)), in the MARCOUF area, fairly large air and sea landings, also landings between VIRE and RAVENOVILLE. The whole area is under own control. The enemy is employing powerful air and naval forces. BARFLEUR and ST. VAAST shelled from the sea. West of LE HAVRE, presumably thrusting towards the TROUVILLE area, there are powerful surface forces consisting of Battleships, cruisers and numerous destroyers.

A further surprise was yet to come: late in the day the Allies launched a second massive airborne drop to reinforce both flanks of the beachhead. 208 gliders carrying 1,347 troops landed in the American zone, as reported here; six minutes later, a further 246 appeared, bound for the British sector. Troops of the 21st Panzer Division, which had earlier pushed towards the coast between Juno and Sword Beaches in the only major counterattack of the day, were demoralised by the sight of the airborne armada; their commanders, wary of being outflanked from the air, ordered them to fall back.

Message reads: MOST IMMEDIATE. Hundreds of gliders are continuously streaming over the North coast of COTENTIN. The first wave landed near ST. VAAST at 2055.

The Marcouf Battery was still holding out, although it had been forced to shell a nearby beachfront ‘resistance nest’ (“WN”) which had been captured by the enemy, and had lost a second gun. For his actions on D-Day, Hennecke recommended Walter Ohmsen for the Iron Cross that very evening. His ordeal was far from over, however; American attacks on 7 and 8 June were repelled, and on 11 June, having finally run out of ammunition, the surviving garrison broke out and reached German lines eight kilometres away. Ohmsen and Hennecke would both be taken prisoner when the Cherbourg garrison surrendered on 29 June.

Message reads: MOST IMMEDIATE. “WN”in front of MARCOUF battery occupied after bombing attack, smoke screen. Embrasure 2 MARCOUF on fire, cannot be extinguished. Suggest IRON CROSS (1st Class) be awarded to S.O. MARCOUF for his outstanding achievements.