Attacking and sinking, or taking as prizes, cargo ships of enemy nations is a practice as old as naval warfare itself. During the Civil War, Confederate commerce raiders sank so many Union merchant ships that the American Merchant Marine never fully recovered from its losses. During World War I, Imperial Germany put several commerce raiders to sea in an effort to disrupt the shipping routes on which Great Britain relied. The first of these were primarily warships. They were costly to operate and difficult to hide from the Royal Navy and they achieved limited success. Most were either sunk or bottled up and made useless by British warships. These were followed by raiders disguised as cargo ships. Their successes were far greater than their predecessors, and most returned home safely after their cruises. With such an approach to naval warfare, ships carrying valuable cargos could be sunk or captured by an unsuspected enemy vessel.
    With the approach of World War II, Grand Admiral Erich RÆder, Commander-in-Chief of the German Kriegsmarine, was faced with a situation where his navy might have to face the Royal Navy with the limited resources available to it. The German rearmament program in the 1930s produced fine battleships, battle cruisers, destroyers, and U-boats. But small numbers could only be built because of the massive resources allocated to the Army and the Luftwaffe. Unable to challenge the supremacy of the Royal Navy, Admiral RÆder relied on a strategy of commerce warfare. Two types of vessels offered the best chance of success to cripple the British lifelines across the seas - U-boats and the disguised surface raiders. The latter, known officially as Auxiliary Cruisers, were in fact cargo ships equipped with an array of surplus World War I weapons capable of challenging most enemy ships, with the exception of larger warships.
    Like pirates and privateers of old days, these ships could sail around the world almost at will, taking on the guise of peaceful cargo ships of almost any nation. These ships, originally built as merchant ships, appeared to an enemy or a neutral as what they had once been. It was only when the German naval ensign, with its large swastika, was raised and the guns were exposed, that their true identity was revealed. By then it was too late. These ships carried a large assortment of flags of many nations that matched the disguises they were able to create by raising or lowering masts and funnels, and altering their profiles with dummy bows and structures.
    These raiders stayed at sea for prolonged times, feeding off captured enemy freighters and tankers, and German supply ships steaming out of Japanese, French, and Italian African ports. They also in turn often supported the U-boat fleet by refueling submarines and restocking them with food and supplies.
    The armament of these ships was almost uniform. They all had six 5.9-inch guns, one 75mm gun, two 37mm antiaircraft guns, and four 20mm automatic cannons. They also carried torpedo tubes and mines. Some of them even had their own aircraft and carried small torpedo boats. However, their greatest assets were their captains and crews. Service on board these auxiliary cruisers was based on volunteers, and their captains were handpicked from the reserve for their cunning abilities to disguise their ships and lead their men for prolonged periods of time without losing efficiency.
    A total of 11 merchant ships were converted for commerce raiding duty. Only nine of them saw action. Their areas of operation covered the North and South Atlantic, Indian Ocean, the vast expanses of the Pacific Ocean, and Antarctica.
    The cost of refurbishing the entire fleet of former merchantmen, generally outfitted with older surplus weaponry, was only one per cent of the cost of constructing a single major warship such as Bismarck or Tirpitz.
    The most famous of these commerce raiders was Atlantis, a ship of 7,860 tons and top speed of 17.5 knots, and enough fuel capacity to sail for 60,000 miles. Under the command of Captain Bernhard Rogge the Atlantis’ cruise lasted for 622 days. She sank or captured 22 ships totaling 145,968 tons. On 22 November 1941, Atlantis’ luck ran out. She was surprised by the heavy cruiser HMS Devonshire northwest of Ascension Island in the South Atlantic. She took heavy pounding from the cruiser’s 8-inch guns, while the cruiser stood out of range of Atlantis’ 5.9-inch guns. Captain Rogge ordered a smokescreen laid, and under its cover his crew set scuttling charges and abandoned ship. The survivors of Atlantis, including Captain Rogge, reached France on 29 December 1941, after being rescued by U-boats. For his achievements, Captain Rogge was awarded the Oak Leaves to his Knight’s Cross.
    One of the most successful raiders, in terms of ships sunk or captured, was Pinguin. During her cruise that lasted for 328 days, she was able to sink and capture 32 ships of 154,710 tons. Her most daring accomplishment was the capture of an entire Norwegian whaling fleet of 14 ships operating near Antarctica. The greatest prize of all was the whale oil - some 20,000 tons of it. There was also another 10,000 tons of fuel oil that could be used by the raider and submarines. On 8 May 1941, the heavy cruiser HMS Cornwall intercepted Pinguin and opened fire on her. The uneven contest could not last for long, one 8-inch shell from the cruiser’s guns penetrated the Pinguin magazines and detonated her mines. Pinguin was carrying 640 crew and prisoners. Of these, only 61 crew and 24 prisoners survived.
    The raider which spent most time at sea was Thor. She conducted two cruises that lasted 653 days and sank or captured 22 ships totaling 152,134 tons. During her first cruise which lasted from 6 June 1940 to 30 April 1941 she sank 12 merchant ships totaling 96,540 tons and covered 57,000 miles. During this cruise Thor encountered three British armed merchant cruisers on three separate occasions. HMS Canarvon Castle, and HMS Alcantara were heavily damaged by Thor’s guns, and HMS Voltaire was sunk.
    On 10 October 1942, Thor docked at Yokohama in Japan for refit and replenishment. While docked at the harbor, a spark ignited fume-filled tanks of one of the tankers docked beside Thor. The resulting explosion and fire destroyed the tanker, Thor and a number of other vessels. Thirteen of the crew were killed, but the captain and the majority of the men survived.
    The next raider which spent more than a year at sea was Michel. This Polish built freighter was converted into an auxiliary cruiser and commissioned into the German Navy on 7 September 1940. Michel set sail on her first cruise on 9 March 1942, and despite a determined attack by British destroyers and motor torpedo boats as she made the hazardous passage down the English Channel, she eventually broke out into the Atlantic on 20 March via the French port of La Pallice. During her two cruises, which lasted for 528 days and covered the south Atlantic, the Indian and Pacific Oceans, she sank 18 ships totaling 127,018 tons. Michel’s luck finally ran out on 17 October 1943, as she approached Yokohama. The raider was stalked by the submarine USS Tarpon, which fired a spread of four torpedoes. Two of these torpedoes hit the raider. The submarine then passed under the ship, came up on the other side and fired a further spread, which blew off the raider completely. Only 110 of the Michel’s crew of 373 men were rescued.
    The story of the raider Kormoran is even remembered to this day in Australia. On 19 November 1941, the raider met the Australian cruiser HMAS Sydney in the waters northwest off the Australian coast. HMAS Sydney was a modern warship in every respect, and it was the pride of the Australian Navy. Kormoran stood no chance against the Australian cruiser which had the advantage of fire power, armor, and speed. During the surprise encounter, a fierce gun battle ensued between the two ships. The raider was able to achieve devastating hits on Sydney’s bridge and front turrets and put a torpedo into her. As a result, the Sydney exploded and was never heard from again. Not a single member of the ship’s crew of 645 men survived. The raider, too, was left dead in the water, and with fires raging, her crew abandoned ship. The survivors, 320 of them from a crew of 400, were rescued, and spent the rest of the war as POWs in Australia. Captain Theodor Detmers, commander of the Kormoran, was awarded the Knight’s Cross in December 1941, which was sent to him via the Red Cross while he was in captivity. During Kormoran’s cruise, which lasted for 352 days, she sank or captured 11 ships totaling 68,274 tons.
    The raider Komet was the smallest of all the raiders. Her displacement was 3,280 tons, and she could barely make 16 knots. Her fuel bunkers, when full, could give her a range of 35,000 miles. Unlike the other raiders, Komet reached her area of operations via the Arctic, aided by Soviet icebreakers. The Nazi-Soviet Non-Aggression Pact was still in force. The Komet sailed via the Barents Sea, on through the Bering Strait and eventually, on 10 September 1940, into the North Pacific. During Komet’s 511 days at sea, her score was seven ships sunk and one taken as prize, for a total of 52,130 tons. On 12 October 1942, Komet was sunk by British destroyers and torpedo boats while trying to break out down the English Channel for her second cruise.
    Not all the raiders were so successful. Stier, after sailing for 142 days and sinking four ships totaling 30,728 tons, encountered the American Liberty Ship SS Stephen Hopkins. She was no match for the Stier. The Stephen Hopkins was only armed with a  few machine guns and a single 4-inch gun. After warning shots fired from Stier, both ships exchanged fire and kept pouring shells into each other until fires on the German raider reached the torpedoes and blew her up. The damage to the Stephen Hopkins was also fatal. She sank and 42 of her crew perished with her. The Stephen Hopkins was the first U.S. ship to sink an enemy surface combat ship in the war.
    From 1940-43, the nine German merchant raiders sank or captured 141 ships for a total of almost a million tons. This by far was the best investment the Kriegsmarine made, compared to the massive building program required to produce the battleships, pocket battleships, and heavy cruisers. Those warships would only account for 60 commercial ships - either sunk or captured.
    In recognition to the effort of these brave seamen of the auxiliary cruisers, Admiral RÆder authorized a special War Badge for them. It was instituted on 24 April 1941.

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