Blücher

Walking through the streets of Oslo, you might come across a ship anchor set up on the Aker Brygge quay(formerly an industrial district of the capital of Norway, now a place famous for its good restaurants, shops, nightclubs and high-standard apartments). I was curious what an ordinary anchor in the city center does, but it turned out that it is not so ordinary. In addition, it is related to the story of a certain German ship.

I assume that the story is an obligatory subject of history lessons in Norwegian schools, but probably not many people outside of Scandinavia have heard of it (maybe except of historians and naval battle enthusiasts). Well, on the anchor placed on Aker Brygge, a modest plate was placed informing that the anchor came from the Blücher unit, which was sunk on April 9, 1940 in the Drøbak narrows.

The given date is the date of the beginning of the German invasion of Norway during World War II, and Blücher was one of the Kriegsmarine ships taking part in it. How did it go down on the first day of the norwegian campaign?

Let us explain first why Hitler decided to attack the neutral Norway. As you probably know, German industry in the 1930s was thriving. Largely thanks to the huge supplies of raw materials, including iron ore from the northern Swedish mining district. A large part of this ore was transported by sea in winter through the Norwegian port of Narvik (the waters around seaports on the Baltic Sea froze in winter). The British saw this as an opportunity to slow the production of Hitler’s military equipment by blockading the port or even occupying Norway. After the Soviet Union attacked Finland in November 1939, the French and British governments began planning to send military help to the struggling Finns. The plan was to land forces in Narvik and capture the Swedish iron ore mining district in the process. The intentions were not implemented, and in March 1940 a peace treaty was signed between Finland and the Soviet Union, which thwarted the strategy of the Allies. The Germans were aware of the actions of the British. They knew that sooner or later they would be able to cut them off from their valuable supply of raw materials. To get ahead of them, Hitler ordered an invasion plan to be drawn up for Norway.

An additional argument involving Hitler in activities aimed at the seizure of Norway was the case of the supply ship Altmark. The German unit operated in the Atlantic in the fall of 1939 together with the cruiser Admiral Graf Spee hunting the British merchant fleet. The British, alarmed by the actions of the German units, sent their forces to track down and sink the German cruiser. On December 13, 1939, the battle known as the Battle of the La Plata River (Rio de la Plata) took place. As a result of the engagement, the badly damaged Admiral Graf Spee was scuttled by the crew. The Altmark, on the other hand, with 303 prisoners from British merchant ships on board (or more precisely below deck, in the holds), eluded the pursuit and headed for Germany. To avoid meeting the ships hunting him, he circled Great Britain from the north and headed to the territorial waters of neutral Norway. Altmark’s captain did not tell the Norwegians that he was transporting prisoners covering up state secrets and a trade flag. The ship was soon located by the British, sending three destroyers to help their countrymen. Altmark took refuge in the Jössingfjord in southern Norway and the British HMS Cossack followed him there, despite the objections of the Norwegian coastal defense forces. There was an exchange of fire and boarding. As a result, several members of the Altmark’s crew were killed and the prisoners held were released. The violation of Norway’s neutrality caused protests from the Norwegian government, but these did not meet with any reaction from the British side, which infuriated Hitler. In addition to accusations against the British, the Germans also blamed the Norwegians for failing to ensure the safety of German sailors (not to mention of course the fact that the Altmark was the first to violate Norway’s neutrality). The Altmark affair thus became an additional catalyst for preparations for the invasion.

In January 1940, the plan for Operation Weserübung was ready. It assumed a quick naval attack on the main ports of the Norwegian coast (Oslo, Bergen, Narvik, Tromsø, Trondheim, Kristiansand and Stavanger), the capture of airfields, the occupation of the country and preparation for an Allied counterattack. Fast German warships were to be used to transport troops. In March, it was decided to extend the invasion plan to capture Denmark, due to the strategically located airports on its territory.

Blücher was the most modern German warship, a heavy cruiser of the Admiral Hipper class. Launched in June 1937 in Kiel, she entered service in September 1939. It had a displacement of 18,500 tons, with main dimensions 203 m long, 22 m width, and had a draft of 7.2 m. It could develop a speed of 32 knots. Her armament consisted of eight 203 mm guns mounted in four rotating turrets, 12 of 105 mm anti-aircraft guns, 12 of 37 mm machine guns, 8 of 20 mm machine guns, and four triple 533 mm torpedo tubes. Small reconnaissance planes could take off from its deck.

The ship was powered by three sets of steam turbines with total 132,000 horsepower.

The ship was entrusted to Captain Heinrich Woldag. He was to lead a group of ships heading for the capital of Norway. The force team was as follows: Blücher as the flagship, heavy cruiser Lützow, light cruiser Emden, and several smaller vessels. An additional 800 soldiers from the 163rd Infantry Division were embarked aboard Blücher. These forces were tasked with capturing the royal family upon reaching the capital and capturing Norway’s gold reserves.

The German fleet heading north was sighted on April 8, 1940, and news of the expected invasion reached Oslo. A government meeting was convened, but it was not decided to announce the army mobilization. For some reason, it was decided that the German ships must rather head towards Iceland and the Faroe Islands. After all, why would they attack of neutral Norway?

On the same day, the Polish submarine ORP Orzeł sank the German SS Rio De Janeiro, carrying German soldiers near Lillesand (southern Norway).The Norwegian authorities were notified of this fact, but even this did not affect the attitude of the Norwegian government.

Late in the evening of April 8, a group of ships heading for Oslo was observed by the Norwegian border guard unit Pol III. A Norwegian captain died, becoming the first casualty of the invasion, when his ship was fired upon by German forces.

The invasion forces entered the Oslofjord heading north towards the Norwegian capital. On the way, they still had to cross the Drøbak narrows, right next to the Oscarsborg fortress located on the island. During the dark, misty night, it was extremely difficult for observers from the shore to identify passing ships. Only a few warning shots were fired from the forts further south, and a message was sent to the commander of Oscarsborg Fortress, Colonel Birger Eriksen, about an unknown group of ships entering the fjord. The fort was not fully manned, and the garrison consisted mainly of recruits who had been sent to the site only a week earlier. Only a few had undergone gun handling training, and the maintenance of the torpedo batteries had been entrusted a month earlier to a retiree who had left the service 13 years earlier. The cannon crew on the other side of the fjord, on the rocky coast of the town of Drøbak, was also put on its feet.

Around four in the morning, on April 9, the defenders of the fortress heard the sounds of powerful ship engines. Colonel Eriksen ordered searchlights to locate the target. Through the thick fog loomed the silhouette of a huge ship. It was Blücher, sailing at the head of the strike group. Eriksen did not hesitate long. He ordered the guns loaded and the first salvo fired at the target. Asked by his subordinates about the warning shot, he replied that these had already been fired from the forts located at the mouth of the fjord a few hours earlier. During the frantic preparations, Eriksen had would say to his men:

„Either I will be court-martialled, or I will become a war hero.”

Then he ordered to open fire. Two 280 mm guns, manufactured in the German Krupp factory (it is ironic that the defenders of the Oscarsberg fortress gave the guns Jewish names: Moses and Aron) fired shells. Both shots hit a target about 1,400m away. The first hit the deck just in front of the aft mast, the second swept the forward gun turret into the fjord. A fire broke out on the ship. Due to staff shortages, the third of the stronghold’s guns was left unattended. Batteries located on land joined the shelling.

Blücher returned fire, but due to the damage, the Germans could only use smaller guns from their arsenal. In the chaos of destruction, however, their actions were ineffective. The crossfire lasted for five to seven minutes as the burning ship passed the fortress.

Just when Captain Heinrich Woldag thought the worst was over and that he might still be able to save the ship, torpedoes were fired from the torpedo battery on the island. Austro-Hungarian Whitehead torpedoes were 40 years old and no one was sure how they would perform in real combat. They turned out perfectly. The first hit close to the forward gun turret without causing much damage. Another hit amidships, tearing a hole in the hull and breaking through the bulkheads inside, damaging the engines. The cruiser stopped at the group of small islands of Askholmene, about 3 kilometers north of Oscarsborg Fortress. Attempts were made to put out the fire consuming the ship. Efforts were in vain when, around 05.30, the fire reached the anti-aircraft ammunition store. The explosion ripped a hole in the hull and tore apart the bulkheads between the boiler rooms and fuel tanks, which only added to the scale of the destruction.

After the first accurate hits from the guns of the fortress, the remaining German units following Blücher withdrew beyond the firing range of the guns, leaving the flagship without fire support.Cruiser Lützow was hit by several shells from the shore batteries before she was able to retreat back into the fog.

At 06.22, Blücher capsized to portside, and soon after turned keel up and began to sink. Oil from damaged tanks was burning on the surface of the fjord. German sailors and infantry embarked before the cruise fought for their lives. Some managed to swim to the shore on their own, some were rescued by Norwegian fishermen who rushed to help as soon as they realized the situation. However, a significant number perished in the flames or drowned in the waters of the Oslofjord. It is estimated that 650-1000 Germans lost their lives that morning.

On the same day, Luftwaffe bombers flew over the Oscarsborg fortress. The raid and firing of the island lasted 9 hours. One of the 42 aircraft was shot down by the defenders and several others damaged.

Oslo was occupied by German forces landing at Fornebu Airport. The infantry landing was carried out at Son, south of Drøbak. In this situation, Colonel Eriksen saw no point in continuing the resistance. He surrendered on April 10 at 9:00 am.

With fortifications more than a century old, manned by recruits and retirees with 40-50 year old guns, a state-of-the-art Kriegsmarine warship was sunk. By delaying the invasion force’s access to the capital by water, the Norwegian administration gained time to flee further north with gold reserves from the Norges Bank. The resistance of the Norwegians lasted until June 10, when the last units surrendered. Today, the Battle of Drøbaksund is seen as Norway’s greatest single achievement during the Second World War, and no other event was of such great military and political importance.

The Wehrmacht took over the fortress and used it as part of the defense forces occupying Oslo. Oscarsborg was in German hands until May 12, 1945.

After the war, Birger Eriksen was awarded the Croix de Guerre and several other decorations.His statue can be seen today on the square in front of the entrance to the fortress building on Oscarsberg Island.

Blücher rests at the bottom of Drøbaksund to this day, at a depth of 64 meters. In 1994, it was decided to remove the oil resources still remaining in the tanks. As a result of a complex operation, 1,000 tons of fuel were pumped out. In 2016, it was decided that the wreck would be a war memorial and it was protected as a cultural heritage. This means that diving and exploration in its vicinity is prohibited. Only the anchor, which proudly displays today on the Aker Brygge pier, and one of the Arado 196 planes that survived the fire were recovered. The latter can be seen at the aviation museum in Sola, near Stavanger.