Invasion of Iceland
On 10 May 1940, during World War II, the United Kingdom landed Royal Navy and Royal Marines forces at Reykjavík and occupied Iceland without resistance. The operation, codenamed Operation Fork, was launched after Germany's rapid conquest of Denmark, to which Iceland was linked by a personal union, and amid British fears that Germany might establish bases on the strategically important island. Iceland had declared neutrality at the start of the war and rejected British requests for cooperation, but the UK proceeded with an unannounced landing to pre-empt any German move.
British troops quickly secured Reykjavík, detained German nationals, and occupied key communication and transport sites before spreading out to potential landing grounds and harbours. Iceland issued a formal protest against the violation of its neutrality, while Britain promised compensation, non-interference, and eventual withdrawal. Over the following months the initial marine detachment was replaced by British, Canadian, and later American forces, whose presence—eventually numbering tens of thousands—had lasting military, economic, and social effects on the country.
Although Germany examined but never executed plans to seize Iceland, the Allied occupation helped secure North Atlantic shipping routes and enabled the establishment of major naval and air bases. Iceland became a republic in 1944, and foreign forces remained until the final withdrawal of US troops in 1947. A treaty signed in 1951 allowed US troops to maintain a presence, which lasted until 2006.
Background
During 1918, after a long period of Danish rule, Iceland had become an independent state in personal union with the Danish king and with common foreign affairs. The new Kingdom of Iceland declared itself a neutral country without a defence force. The treaty of union allowed for a revision to begin during 1941 and for unilateral termination three years after that, if no agreement was made. By 1928, all Icelandic political parties were in agreement that the union treaty would be terminated as soon as possible.On 9 April 1940, German forces began Operation Weserübung, invading both Norway and Denmark. Denmark was subdued within a day and occupied. On the same day, the British government sent a message to the Icelandic government, stating that the UK was willing to assist Iceland in maintaining its independence but would require facilities in Iceland to do so. Iceland was invited to join the UK in the war "as a belligerent and an ally." The Icelandic government rejected the offer. On the next day, 10 April, the Icelandic parliament, the Alþingi, declared Danish King Christian X unable to perform his constitutional duties and assigned them to the government of Iceland, along with all other responsibilities previously performed by Denmark on behalf of Iceland.
With Operation Valentine the British occupied the Faroe Islands, on 12 April 1940. After the German invasion of Denmark and Norway, the British government became increasingly concerned that Germany would soon try to establish a military presence in Iceland. They felt that this would constitute an intolerable threat to British control of the North Atlantic. Just as strategically important, the British were eager to obtain bases in Iceland to strengthen their Northern Patrol.
Planning
As the military situation in Norway deteriorated, the Admiralty came to the conclusion that Britain could no longer do without bases in Iceland. On 6 May, Winston Churchill presented the case to the War Cabinet. Churchill maintained that if further negotiations with the Icelandic government were attempted, the Germans might learn of them and act first. A surer and more effective solution was to land troops unannounced and present the Icelandic government with a fait accompli. The War Cabinet approved the plan but the expedition was mounted in a rush. Much of the planning was conducted en route; the force was supplied with few maps, most of poor quality, with one of them having been drawn from memory. No one in the expedition was fully fluent in Icelandic.The British planned to land all of their forces at Reykjavík. There, they would overcome any resistance and defeat local Germans. To guard against a German counter-attack by sea, they would secure the harbour and send troops by land to nearby Hvalfjörður. The British were also worried that the Germans might airlift troops, as they had done with great success in their Norwegian campaign. To guard against this, troops would drive east to the landing grounds at Sandskeið and Kaldaðarnes. Troops would also be sent by land to the harbour at Akureyri and the landing ground at Melgerði in the north of the country.
The UK Naval Intelligence Division expected resistance from three possible sources. Local Germans, who were thought to have some arms, might resist or even attempt some sort of coup. A German invasion force might already be prepared or begun immediately after the British landings. The NID also expected resistance from the Reykjavík police, consisting of some 60 armed men. If by chance a Danish patrol vessel were present in Reykjavík, the Danish sailors might assist the defenders. The only Danish naval vessels abroad were in Greenland.
Operation Fork
Force Sturges
On 3 May 1940, the 2nd Royal Marine Battalion in Bisley, Surrey received orders from London to be ready to move at two hours' notice for an unknown destination. The battalion had been activated only the month before. Though there was a nucleus of active service officers, the troops were new recruits and only partially trained. There was a shortage of weapons, which consisted only of rifles, pistols, and bayonets, while 50 of the marines had only just received their rifles and had not had a chance to fire them. On 4 May, the battalion received some modest additional equipment in the form of Bren light machine guns, anti-tank rifles, and 2-inch mortars. With no time to spare, zeroing of the weapons and initial familiarisation shooting would have to be conducted at sea.Assisting arms provided to the force consisted of two 3.7-inch mountain howitzers, four QF 2-pounder anti-aircraft guns, and two QF 4-inch coastal defence guns. The guns were manned by troops from the artillery divisions of the Navy and the marines, none of whom had ever fired them. They lacked searchlights, communication equipment, and gun directors.
Colonel Robert Sturges was assigned to command the force. Aged 49, he was a highly regarded veteran of World War I, having fought in the battle of Gallipoli and the battle of Jutland. He was accompanied by a small intelligence detachment commanded by Major Humphrey Quill and a diplomatic mission managed by Charles Howard Smith. Excluding those, the invasion force consisted of 746 troops.
Journey to Iceland
On 6 May, Force Sturges boarded trains for Greenock on the Firth of Clyde. To avoid drawing attention to itself, the force was divided into two trains for the journey, but due to delays in rail travel, the troops arrived at the railway station in Greenock about the same time, losing the small degree of anonymity desired. Additionally, security had been compromised by a dispatch uncoded and by the time the troops arrived in Greenock, many people knew that the destination was Iceland.On the morning of 7 May, the force headed to the harbour in Greenock, where they met the cruisers and, which would take them to Iceland. Boarding commenced but was fraught with problems and delays. Departure was delayed until 8 May, and even then a large amount of equipment and supplies had to be left on the piers.
At 04:00 on 8 May, the cruisers departed for Iceland. They were accompanied by an anti-submarine escort consisting of the destroyers and. The cruisers were not designed to transport a force of the size assigned to them, and conditions were cramped. Many of the marines developed severe seasickness. The voyage was used as planned for calibration and familiarisation with the newly acquired weapons. One of the newly recruited marines died by suicide en route. The voyage was uneventful otherwise.
Surprise is lost
At 01:47, Icelandic time, on 10 May, HMS Berwick launched one of its Supermarine Walrus reconnaissance aircraft from its aircraft catapult. The principal aim of the flight was to scout the vicinity of Reykjavík for enemy submarines, which the Naval Intelligence Division had convinced itself were operating out of Icelandic harbours.The Walrus was given orders not to fly over Reykjavík but – either accidentally or as the result of a miscommunication – it flew several circles over the town, making considerable noise. At this time, Iceland possessed only passenger aircraft, which did not fly at night, so this unusual event awoke and alerted a number of people. The Prime Minister of Iceland Hermann Jónasson was alerted about the aircraft, as were the Icelandic Police. The acting chief of police, Einar Arnalds, surmised that it most likely originated from a British warship bringing the expected new ambassador. This was correct, though it was not the whole story.
, the German consul, was also alerted to the aircraft. Suspecting what was about to happen, he drove down to the harbour with a German associate. With the use of binoculars, he confirmed his fears and then hurried back. At home, he arranged for the burning of his documents and tried unsuccessfully to reach the Icelandic foreign minister by telephone.
Down at the harbour
At 03:40, an Icelandic policeman saw a small fleet of warships approaching the harbour, but could not discern their nationality. He notified his superior, who notified Einar Arnalds, the acting chief of police. The laws of neutrality to which Iceland had committed forbade more than three warships from a belligerent nation from making use of a neutral harbour at the same time. Any aeroplanes from such ships were forbidden from flying over neutral territorial waters. Seeing that the approaching fleet was about to violate Icelandic neutrality in two ways, Arnalds began to investigate. Down at the harbour, he viewed the ships for himself and decided they were probably British. He contacted the foreign ministry, which confirmed that he should go out to the fleet and announce to its commander that he was in violation of Icelandic neutrality. Customs officers were ordered to prepare a boat.Meanwhile, marines on Berwick were being ordered aboard Fearless, which would take them to the harbour. The seasickness and inexperience of the troops were causing delays and the officers were becoming frustrated. Just before 05:00, Fearless, loaded with about 400 marines, began moving toward the harbour. A small crowd had assembled, including several policemen still waiting for the customs boat. The British consul had received advance notice of the invasion and was waiting with his associates to assist the troops when they arrived. Uncomfortable with the crowd, Consul Shepherd turned to the Icelandic police. "Would you mind... getting the crowd to stand back a bit, so that the soldiers can get off the destroyer?" he asked. "Certainly," came the reply.
Fearless started disembarking immediately once it docked. Arnalds asked to speak with the captain of the destroyer, but was refused. He then hastened to report to the Prime Minister, who ordered him not to interfere with the British troops and to try to prevent conflicts between them and Icelanders. Down at the harbour, some of the locals protested against the arrival of the British. One Icelander snatched a rifle from a marine and stuffed a cigarette in it. He then threw it back to the marine and told him to be careful with it. An officer arrived to scold the marine.