On 14 August 1914 Vice Admiral Maximilian von Spee detached Fregattenkapitän Karl von Müller’s light cruiser SMS Emden (3,664 tons, 23.5 knots, 10 x 4.1 inch and 8 x 2 inch guns, 2 x 17.7 inch torpedo tubes) and the supply ship Markomannia from his East Asia Squadron to operate in the Indian Ocean. Spee wrote in his war diary that:
A single light cruiser, which consumes far less coal and can, if necessary, coal from captured steamships, will be able to maintain herself longer than the whole Squadron in the Indian Ocean, and as there are great prizes to be won there (Indian, East Asiatic and Australian shipping), it seems advisable to despatch our fastest light cruiser, the Emden, with our best collier. She can subsequently proceed to the African coast, or should Holland remain neutral, to the Netherland East Indies.
However, the Dutch decided to ‘rigorously enforce their neutrality.’ On 27 August the Dutch coast defence ship Tromp ordered Emden to stay out of Dutch territorial waters. She had earlier sent away a German collier that had stayed too long in Dutch waters. This meant that the Germans had to abandon their pre-war plan that supply ships should wait for orders in neutral waters. Emden’s coal bunkers had a capacity of 790 tons. She might carry up to 1,000 tons, but her combat efficiency and the crew’s living conditions would be adversely affected by the need to store coal wherever space could be found. At her most economical cruising speed of 12 knots she consumed 60 tons of coal an hour. At the maximum speed that she managed on trials of 23.85 knots she used 371 tons per hour. Thus, with a normal coal load, she had an endurance of just over 13 days and a range of just under 3,800 miles at 12 knots. She could maintain full speed for about 50 hours and 1200 miles. Müller used the following tactics when attempting to capture a merchantman: The commerce raider should not show its colours until the last moment; it should raise the signals “Stop” and Do not use your wireless” along with its ensign; as little use as was possible should be made of searchlights; and the raider should take up a position that made it impossible for it to be rammed by the merchant ship. He also recommended that cruisers employed as commerce raiders should have larger than normal crews in order to be able to provide prize crews for colliers and guards for prisoners. Secrecy was vital for a commerce raider, but the disappearance of merchant ships and reports from neutral ships would mean that the enemy would discover the cruiser’s operating area. Consequently, delaying landing prisoners at ports would help preserve secrecy only if the cruiser had not stopped any neutral ships or if it was operating a long way from enemy signal stations or ports. Emden’s appearance on the Colombo to Calcutta route in the Bay of Bengal surprised the British. They had returned to peacetime procedures, as they had not realised that Spee had detached one of his cruisers. Consequently, her early victims assumed that she was a British cruiser. Müller encouraged this by having a fake fourth funnel rigged. British light cruisers had two or four funnels, whereas Emden had three. Emden coaled at Simular Island off Sumatra on 5 September, narrowly missing the armoured cruiser HMS Hampshire, which had searched there the day before.
On 10 September, Emden stopped a neutral ship, the Greek Pontoporos, whose cargo of coal was British, making her a legitimate target. Müller kept her as a collier. Emden had captured five British ships by 13 September. One, the Kabinga, had a US cargo, so was retained as a prison ship. The other four were sunk. The next ship intercepted by Emden was another neutral, the Italian Loredano. Her master, Captain Giacopolo, refused to take Emden’s prisoners on board on the grounds that his ship had insufficient provisions. Müller allowed her to go. She did not have a wireless, but the next day met and warned the City of Rangoon, a new ship carrying a cargo worth £600,000, which did have a wireless. This led to a suspension of trade, which meant that several ships that would probably have been caught by Emden remained in Calcutta: she was then very close to that port. She did, however, capture and sink another merchantman that had already sailed. Müller now decided to change his area of operations. He first sent the Kabinga to Calcutta (now Kolkata), with his prisoners, before heading for the coast of Burma (now Myanmar). On the way, Emden captured and sunk another British ship, transferring her crew to a Norwegian ship on 16 September Müller’s next move, after coaling, was to attack Madras (now Chennai) after dark on 22 September. Some damage was caused to the steamer Chupra and to the town, but the main damage caused by the attack was the destruction of 425,000 gallons of oil in the Burmah Oil Company’s tanks. It also led to an interruption of trade in the Bay of Bengal at 2 am on 23 September, only 18 hours after the previous suspension had been lifted, and to alarm in Madras and the surrounding area. Five people were killed and a dozen wounded. Between 25 and 27 September Emden took six prizes in the area of Ceylon (now Sri Lanka). Three were in ballast, but the Admiralty collier Buresk carried 6,000 tons of Welsh steam coal, the best coal in the world for naval use. Buresk was retained as a collier, four of the ships were sunk and the sixth sent to Colombo with the prisoners. Emden then coaled in the Maldives, before arriving at Diego Garcia on 9 October to carry out repairs. Diego Garcia is still British territory and is now a major US base, but it was then so remote that its inhabitants had not learnt of the war. However, on 12 October the light cruiser HMS Yarmouth sank the Markomannia and removed the Pontoporos from German control. Müller next took his ship back to Ceylon, capturing seven merchantmen from 16 to 19 October. Five were sunk and another sent to port with the prisoners. The sixth, the Exford, was retained as she was another Admiralty collier carrying 6,000 tons of Welsh tons. On 21 October Emden passed within 10-20 miles of Hampshire and the armed merchant cruiser HMS Empress of Asia, but the ships did not see each other because of poor visibility. At 5:00 am on 28 October, Emden entered Penang, which had no fixed defences, but was defended by three French destroyers and a torpedo boat. The Russian protected cruiser Zhemchug was also present (3,103 tons, 24.5 knots, 8 x 4.7 inch and 4 x 1.9 inch guns, 4 x 18 inch torpedo tubes): she was smaller than Emden, but not hugely outclassed. Emden was initially assumed to be a British cruiser and did not raise German colours until she was three quarters of a mile from the Zhemchug. Emden then fired a torpedo at her, closed to 800 yards and opened fire.
The Allied ships were caught unprepared. Emden sailed passed the French ships, turned and fired another torpedo into the Zhemchug, which sank 15 minutes after the start of the action. 91 of her crew of 340 were killed and 108 wounded. Emden tried to capture the steamer Glenturret, which was waiting for a pilot and was flying a flag that indicated that she was carrying explosives. However, the French destroyer Mousquet then returned from patrol. She was quickly overwhelmed by Emden and sank in seven minutes. The Germans picked up the French survivors, but then left, as the other French destroyers had now been alerted. Müller learnt from his prisoners that he had lost Pontoporos before he put them onto a merchant ship that he captured soon after leaving Penang. On 1 November a large convoy carrying Australian and New Zealand troops to Egypt left King George Sound, Albany, Western Australia. It was escorted by the Japanese battlecruiser Ibuki (14,636 tons, 21.5 knots, 4 x 12 inch, 8 x 8 inch, 14 x 4.7 inch and 4 x 3.1 inch guns, 3 x 18 inch torpedo tubes), the British armoured cruiser HMS Minotaur (14,600 tons, 23.1 knots, 4 x 9.2 inch, 10 x 7.5 inch and 16 x 12 pounder guns, 5 x 18 inch torpedo tubes) and the Australian light cruisers HMAS Melbourne and Sydney (each 5,400 tons, 25.5 knots, 8 x 6 inch and 4 x 3 pounder guns, 2 x 21 inch torpedo tubes). On 8 November Minotaur received an order to join the Cape Squadron in South Africa in place of the pre-dreadnought battleship HMS Goliath, which had suffered mechanical problems. The Admiralty by then knew that Spee’s squadron was in the south Pacific, so the only threats to the Australasian Convoy were Emden and Königsberg. That day Emden and Buresk were meeting Exford 40 miles north of the Cocos Islands. The next day Emden appeared at Direction Island, landing about 50 men under Kapitänleutenant Hellmuth von Mücke to destroy the wireless station. However, the fourth funnel had been poorly rigged, so the wireless station personnel realised that Emden was German and sent a warning. The convoy was 55 miles north of the Cocos just before 7:00 am when it received the warning. Captain M. L. Silver of Melbourne, the escort commander, was not allowed to detach his own ship, and decided that his must retain his most powerful one, Ibuki, in case the two German cruisers combined to attack the convoy. He therefore sent Sydney to the Cocos. On the morning of 9 November Emden saw smoke, which was assumed to be the Buresk. However, it soon became clear that it came from a four funnelled cruiser. She was Sydney, One of Emden’s officers assumed initially that she was either HMS Newcastle or Yarmouth, which both operated in the area. He later wrote that he was ‘pleased’ about this, which is rather puzzling. Yarmouth was as strong as Sydney and Newcastle outgunned Emden, though not overwhelmingly (4,800 tons, 25 knots, 2 x 6 inch, 10 x 4 inch guns, 4 x 3 pounder guns, 2 x 18 inch torpedo tubes). Müller thought that she was Newcastle. Müller ordered his ship to raise steam. There was not time to recover the landing party, and Emden left the lagoon entrance at 9:17 am. Müller wanted space in which to manoeuvre. Emden opened fire at 9:40 am at a range of 9.500 yards and soon scored hits, but her 4.1 inch guns could do little damage at that range. Sydney initially over estimated the range, so did not hit until her 12th round. Her actual speed advantage was more like 4 knots than the theoretical 2 knots, so her captain, John Glossop, was able to keep his ship out of the Emden’s effective range whilst causing heavy damage to the German cruiser. Early in the action, Emden lost her forward funnel and her steering gear, forcing her to steer with her engines. Sydney closed to 5,500 yards in order to launch a torpedo, which missed. She then opened the range. Müller tried a torpedo attack but could not get close enough By 10:20 am Emden had lost all three funnels and both her fire control positions. She was holed both fore and aft and the amount of smoke coming from her led Sydney to think briefly that she had sunk. The unequal action continued until 11:20 am, when it became obvious that Emden was sinking. She ran herself aground on the reef of North Keeling Island. Sydney then headed off in pursuit of Buresk. A prize crew boarded her, but the Germans had already opened her scuttles, and she was sinking. Sydney then returned to North Keeling Island and at 4:00 pm started firing on Emden, which was still flying her ensign because the lines that were used to raise and lower it had been shot away. Müller ordered his crew to abandon ship, but many were drowned as they tried to swim ashore. Sydney ceased fire after a white flag was shown and Seaman Werner climbed the mast to lower the ensign. This was the Royal Australian Navy’s first victory over a warship. Müller was unhappy that Sydney fired on a helpless ship. However, there were plenty of examples of both sides in this war carrying on firing on enemy ships until they struck their colours, including SMS Nürnberg on HMS Monmouth at Coronel eight days before. Sydney then returned to Direction Island with the intention of capturing the landing party, first picking up the survivors of Emden who were in the water. When she reached the station, the landing party had sailed away in the proprietor’s schooner, Ayesha. The schooner became SMS Ayesha and managed to reach Arabia, then part of the Ottoman Empire. One man died of typhus and others were killed in skirmishes with Bedouin tribesmen. The 49 survivors travelled by the Hejaz Railway to Constantinople, where on 23 May 1915 they were welcomed by the German commander of the Ottoman fleet, Admiral Wilhelm Souchon. They were the only men from Germany’s two German and six light cruisers outside European waters at the outbreak of war to reach friendly territory with colours flying.  On 10 November Sydney returned to North Keeling Island to rescue Emden’s survivors. 134 of her crew had been killed in the battle and four of the 66 wounded prisoners died of their wounds. 145 men were captured unwounded. Sydney had four men killed and 122 wounded. More of Emden’s crew were captured when Sydney boarded Buresk and when HMS Himalaya re-captured the Exford in December. Sydney lost four men killed and 12 wounded. Müller was much admired by both sides. Winston Churchill, the First Lord of the Admiralty, ordered that:
‘The captain, officers and crew of the Emden have earned the most honourable treatment possible under the rules of war. If there are no incidents that would preclude otherwise, the captain and his officers may retain their daggers.’
This was equivalent to allowing army officers to keep their swords, but the daggers had been lost with the ship. The Official History of the RN in WWI praised Müller for his ‘skill, resource and boldness…and for the chivalry and humanity with which his duty had been discharged.’ Emden was one of only two German warships in WWI whose entire crew were awarded the Iron Cross Second Class, the other being the submarine U9. Müller was awarded Germany’s highest decoration, the Pour le Mérite, popularly known as the Blue Max, in 1918. By then, the British had allowed him to go first to the Netherlands and then back to Germany on the grounds of poor health. He had previously been awarded the Iron Cross First Class, but this medal had become more common since 1914, so a higher award was by 1918 thought to be more appropriate. Emden was the most successful of the German cruisers employed as commerce raiders. She destroyed 16 merchantmen with a total tonnage of 82,938 tons, and also sank two Allied warships. This was not greatly superior to the 76,609 tons of merchant shipping destroyed by Karlsruhe, but Emden caused far more disruption to British trade. Karlsruhe operated off the north east coast of Brazil and did not cost the British much more than the value of the ships that she sank. Emden caused trade in the Bay of Bengal to be suspended from 14 September to 2 October, apart from brief periods on 22-23 September and 1 October. An average of one Japanese battlecruiser, four armoured cruisers, four light cruisers and two armed merchant cruisers were searching for Emden at any one time. The final word on Müller and Emden should go to the German Official History:
‘Müller delivered his blows where they would have the greatest political and economic effect. His sudden appearance and disappearance at the scene of operations and a correct appreciation of the enemy’s counter moves enabled him not only to achieve success in each individual operation, but also to render his capture difficult. It was not luck, but the capacity for forming an accurate estimate of the situation from the scanty information obtainable from prizes and intercepted wireless, that were responsible for his achievements in spite of all the enemy’s endeavours to catch him. Far from keeping to any fixed scheme, Captain Von Müller instantly dropped a predetermined course of action when circumstances rendered a change of plan desirable.’
 Technical details of warships are from R. Gray, Conway’s All the World’s Fighting Ships, 1906-1921 (London: Conway Maritime Press, 1985). unless otherwise stated.  Naval Staff Monograph (Historical) Review of German Cruiser Warfare 1914-1918. p. 4.  P. G. Halpern, A Naval History of World War I (London: UCL Press, 1994), p. 74.  Gray, Conway’s 1906-1921, p. 157; R. K. Lochner, The Last Gentleman-of-War : The Raider Exploits of the Cruiser Emden, trans., T. Lindauer, H. Lindauer (Annapolis, MD: Naval Institute Press, 1988), p. 307., where the coal consumption is stated to be 60 tons a day at 12 knots. An alternative of 48 tons a day is given on p. 16, but the higher figure is the same as used by Gray.  German Cruiser Warfare. p. 7.  Lochner, Last Gentleman, p. 73.  C. E. Fayle, Seaborne Trade., 3 vols. (London: HMSO, 1920). vol. i, p. 207.  Ibid., pp. 209-11.  Ibid., p. 213.  J. S. Corbett, H. Newbolt, Naval Operations, 5 vols. (London: HMSO, 1938). vol. i, p. 334.  See Wikipedia entry linked to ship’s name in text above. <<http://en.wikipedia.org/wiki/Russian_cruiser_Zhemchug>>. Accessed 10 November 2014.  P. H. Silverstone, Directory of the World’s Capital Ships (London: Ian Allan, 1984), p. 182.  UK National Archives, Kew, ADM 137/10221, ‘S.M.S. Emden: Later Papers’. ‘Account by Officer ex S.M.S. EMDEN of SYDNEY-EMDEN Action 9/11/14’, p. 272 says the landing party was 53 men, with a total of about 60 including boat crews; Lochner, Last Gentleman. says 50, p. 213.  ADM 137/1021, p. 273.  A. W. Jose, The Official History of Australia in the War of 1914-1918, vol. ix, the Royal Australian Navy, 1914-1918, Ninth ed. (Sydney: Angus and Robertson, 1941), p. 195.  Corbett, Newbolt, Naval. vol. i, p. 382.  ADM 137/1021, p. 273.  Lochner, Last Gentleman, pp. 184-85.  Jose, R.A.N., pp. 200-1.  Ibid., pp. 188-89.  Lochner, Last Gentleman, pp. 279-80.  Corbett, Newbolt, Naval, p. 384.  Quoted in Lochner, Last Gentleman, p. 207.  Corbett, Newbolt, Naval. vol. i, p. 385.  German Cruiser Warfare. p. 8.  Quoted in Ibid.