While the western front remained strangely quiet, a new conflict erupted in northeastern Europe. Though something of a sideshow, it soon attracted the attention of Germany and the Allies and led indirectly to another clash of arms in the far northwestern reaches of the continent.
THE RUSSO-FINNISH WAR
The initial northern conflict became known as the Russo-Finnish War (Winter War) and raged from November 30, 1939 to March 14, 1940. It resulted from Finland's refusal to grant certain concessions that the Soviet Union demanded in the fall of 1939. The Soviet demands reflected Stalin's fear that Finland might fall under German influence. Leningrad, Russia's second-largest city, lay only 20 miles from the Finnish border on the Karelian Isthmus, a narrow neck of land that separated the Gulf of Finland on the west from Lake Ladoga on the east. It was within range of Finnish artillery. The Soviets insisted that the Finns cede a portion of the Karelian Isthmus to Russia, thus freeing Leningrad from the threat of artillery bombardment. This revision would have left Finland's chief defensive system, the Mannerheim line, in Soviet hands. The Soviets also requested other changes, including a 30-year lease on the port of Hango for use as a Russian naval base. Hango was less than 100 miles from Helsinki, the Finnish capital. In return for these concessions, Moscow offered to give Finland twice as much territory to the north of Lake Ladoga. The Finns agreed to most of the Soviet demands but refused the Hango lease, contending that it was incompatible with their independence and neutrality to allow a foreign base on their territory.
Stalin responded to the Finnish refusal by sending a force of 30 divisions and six tank brigades across the border against a total of only nine Finnish divisions. Before the campaign ended, the Russians committed a total of 45 divisions. An overwhelming Soviet victory seemed certain. But the Russians had not anticipated their own bungling or the astonishingly heroic and effective Finnish resistance under the leadership of 72-year-old Field Marshal Carl von Mannerheim. Mannerheim had served as a cavalry officer in the army of the Russian tsar. But he took advantage of Russia's weakness in 1918 to lead Finland to independence and defeated the Soviet-backed Red forces in a Finnish civil war. As chairman of the Council of National Defense in 1933, he was responsible for constructing the fortifications that bore his name.
Finnish troops not only halted the Russian offensive but annihilated five Soviet divisions. The Russians had committed the blunder that the Germans had managed to avoid on the western front - an attack in the dead of winter. Although the Mannerheim line was not especially strong, the Red Army encountered difficulty with the forests, swamps, and lakes that abounded in the Karelian Isthmus, and its efforts to achieve a breakthrough failed miserably.
But far greater disasters befell the Russians when they attacked at several points to the north of Lake Ladoga in areas characterized by dense forests, thousands of lakes, few roads, and heavy snow. Soviet commanders ordered their troops deep into the frozen wastes. Russian mechanized forces, which were quite unsuited for this type of warfare, became strung out in long columns extending for many miles that offered inviting targets for Finnish troops wearing white uniforms and operating on skis. The Finns, gliding like ghosts through the snow, cut Soviet supply lines and ambushed isolated enemy forces. Russian troops also suffered terribly from the cold as temperatures fell as low as 30 degrees below 0 Fahrenheit. They even lacked "trigger finger" mittens and had to bear their hands to fire their weapons. When the Finnish attacks ended, thousands of frozen Soviet corpses littered the roads and forests of east-central Finland. Observers noted that the bodies were as hard as petrified wood with skin the color of mahogany.
By early January 1940, it was clear that the Russians had failed. Stalin now appointed Marshal Semyon Timoshenko to command the Finnish front. A Ukrainian, Timoshenko had served as a noncommissioned officer in the tsarist army during World War I but became a Red Army officer in the Russian civil war. Though not a brilliant commander, he was far superior to the inept Marshal Klementi Voroshilov, one of Stalin's close associates, who had directed the abortive operations against Finland in December. Timoshenko abandoned the ill-advised attacks north of Lake Ladoga and concentrated on breaking through the Mannerheim line. He carried out a massive buildup throughout January and finally opened his offensive on February 11. The Russians outnumbered the Finns 50 to 1 and had an enormous advantage in equipment. By early March, they had broken through the Mannerheim line. The Finns, realizing that they were at the end of their resources and fearing an imminent Soviet drive on Helsinki, asked for an armistice on March 12.
The peace terms were more severe than the original Soviet demands. Most important, they required the Finns to cede the entire Karelian Isthmus as well as all their other territory along the shores of Lake Ladoga. Finland also granted the lease on Hango. But the Soviet Union, a great power of 175 million people, had little reason for jubilation. Though ultimately victorious, it had suffered repeated humiliations at the hands of a nation of barely 4 million. Hitler, who had been dubious about Russian power all along, was now convinced that his neighbor to the east was no match for the Wehrmacht. The Winter War contributed significantly to his underestimation of the USSR as an enemy a year later. The Soviets, however, now set out to remedy the glaring weaknesses that the conflict had exposed in their military machine. And, although progress was far from complete when Hitler attacked them in 1941, their efforts ultimately did pay dividends.
The Finnish campaign had an important byproduct - the opening of all of Scandinavia as a potential theater of operations. British and French leaders were filled with admiration for the gallant Finnish resistance and actually contemplated sending a small military force to help Finland. They also considered bombing the oil fields of the Caucasus Mountains. In view of the Western Powers' reluctance to take military action to help Poland, it is really quite astonishing that they should have considered such a foolhardy undertaking on behalf of Finland. It would have meant war with the USSR at the same time that the Allies faced the threat of a German offensive in the west. Furthermore, such limited aid would not have made the slightest difference in the final outcome of the Winter War. The Allied attitude revealed the extent of anti-Soviet feeling in both Britain and France.
If they were to provide direct assistance to Finland, the Allies needed to secure passage for their troops through neighboring Norway and Sweden, but the Norwegians and Swedes refused to grant permission. The Allies also hoped to occupy the mines of northern Sweden, which provided the Germans with 40 percent of their iron ore supply. Much of the ore reached Germany from the port of Lulea on the Gulf of Bothnia, an arm of the Baltic, but the gulf froze during the winter, necessitating shipments by rail to Narvik on Norway's Atlantic coast. From Narvik, the precious ore went by ship through the Norwegian Leads, a sheltered passage between the highly indented coast and the open sea. Winston Churchill, now Britain's first lord of the admiralty, had urged the mining of the Leads to interfere with German ore shipments as early as September 1939.
Germany also coveted Norway as the world's only source of heavy water, which was produced at the Norsk hydroelectric plant in the southern town of Vemork. German scientists hoped to use heavy water as a moderator in a nuclear reactor that might lead to the creation of an atomic bomb. In heavy water the hydrogen atoms of ordinary water are replaced by atoms of heavy hydrogen (deuterium), giving the water a different chemical formula as well as different physical characteristics, including greater weight.
FOCUS ON SCANDINAVIA
Although the conclusion of the Winter War ended the possibility of sending troops to Finland, Churchill and other Allied leaders persisted in plans to mine the Leads. They also assumed that such action would provoke Hitler to undertake an invasion of Norway, and at the first indication of this, they planned to occupy Narvik and the other major ports on Norway's Atlantic coast. But for all of their various schemes for intervention in Scandinavia, the Allies seriously underestimated the number of troops they would need to carry out such an operation. They were also skeptical of Germany's ability to invade Norway successfully in the face of superior British naval power.
Hitler worried about Allied intentions in Scandinavia during the Winter War and became especially concerned about the potential disruption of Swedish iron ore shipments to Germany. In December, he ordered preliminary planning for the possibility of a preemptive German invasion of not only Norway but Denmark as well.
An incident occurred in February that helped persuade Hitler that a Scandinavian operation was necessary. On the night of February 16, the British destroyer Cossack intercepted the German tanker Altmark in Norwegian territorial waters. A party from the Cossack boarded the Altmark and rescued 300 British prisoners, the survivors from a number of ships that the German surface raider Graf Spee had sunk during the first few months of the war. The Graf Spee's commander had transferred the prisoners to the Altmark. The Altmark affair convinced Hitler that Britain would not respect Norwegian neutrality. Two days later, he ordered invasion preparations to be accelerated, and on March 1 he issued a formal directive for an attack on Denmark and Norway.
Hitler gave the OKW sole responsibility for the Scandinavian enterprise, and the OKH had no part in its development. It was the only major German campaign of the war that combined land, sea, and air operations in which the navy played a decisive role. Hitler appointed General Nikolaus von Falkenhorst, who had commanded a corps in the Polish campaign, to direct the invasion. With the bulk of German strength earmarked for the invasion of Western Europe in May, Falkenhorst had only limited forces at his disposal. But he used them boldly and skillfully when the Scandinavian operation began on April 9.
THE CONQUEST OF DENMARK AND NORWAY
Denmark's meager army of 15,000 men was no match for the Germans, who caught the Danes completely by surprise and overran the country in a matter of hours. The Germans also enjoyed the advantage of surprise when they landed in Norway. The Norwegian defensive forces were small and seriously deficient in modern equipment, especially aircraft.
The invasion of Norway was an extremely risky undertaking. It involved transporting troops not only across the Skagerrak, the relatively narrow body of water between Denmark and Norway, but into the Atlantic as well in the face of British naval supremacy. The German plan called for landings at all major Norwegian ports - Oslo and Kristiansand on the Skagerrak and Bergen, Stavanger, Trondheim, and Narvik on the Atlantic coast. Allied naval units had laid mines in Norwegian coastal waters the day before the invasion and were still nearby. The British could also intervene with their home fleet, which was stationed in Scapa Flow to the north of Scotland. In addition, they maintained a small military force that was to seize Norway's major Atlantic ports if the Germans showed any indication of retaliating for the British mine-laying operation.
When the Germans actually launched their invasion fleet, British planes spotted German naval forces heading northward as early as the morning of April 7. But when the home fleet sailed seven hours later, its commander decided to leave the military force behind despite the plan to seize the Norwegian ports. British naval units were also uncertain of the exact location or destinations of the German invasion forces. To make matters worse, a savage storm impeded their search for the elusive enemy. Although elements of the rival fleets engaged in isolated skirmishes, no all-out battle took place, and the Royal Navy did not seriously interfere with the German landings.
Speed, precision timing, and luck all contributed to Germany's success. The OKW scheduled each landing to take place at approximately the same time. The first troops to land traveled on fast warships, which penetrated quickly into each port, and disembarked in most cases before the Norwegians could react. Reinforcements followed in slower transports. The initial invasion forces did not total more than 10,000 men, and the largest number at any one port was approximately 2,000. The Germans did not use panzer units, which were not well suited for the mountainous Norwegian terrain. But they did employ small numbers of tanks to support the infantry, and the armor performed well in this role.
The only serious threat to the invasion came at Oslo, where for a time the fate of the entire operation seemed to hang in the balance. Oslo lay at the northern end of Oslofjord, the body of water that linked the capital with the Skagerrak. At the fjord's narrowest point, the old but formidable Oscarsborg fort guarded the approach to Oslo with 11-inch guns and torpedo defenses. These weapons combined to sink the new German cruiser Blucher when the invasion flotilla attempted to penetrate beyond the Oscarsborg. Confronted by this disaster, the other German ships turned back and disembarked their troops about 20 miles from Oslo.
The success of the assault now depended on a projected airborne seizure of the airfield outside the capital. Once the Germans had accomplished this, they planned to strengthen their initial force with troops ferried in by transport planes. But fog over southern Norway prevented them from carrying out the airborne operation. If the Norwegians had made a vigorous attempt to defend the capital and its airfield at this crucial point, they might have badly disrupted the German timetable. Instead, they abandoned the city without a fight. A small unit did try to hold the airfield, but a few German fighter planes managed to land, and the pilots, using their machine guns, held the defenders at bay until transports arrived with reinforcements. These troops quickly marched on Oslo and occupied the city.
Oslo was the key to the invasion. The Germans quickly moved out from the capital to link up with troops at other ports, who were simply to hold their positions until the relief expeditions arrived. With the exception of the force at Narvik, all carried out their missions successfully. Narvik lay too far north. In the days following the landing there, British destroyers and the battleship Warspite sank 10 German destroyers and gained complete control of the neighboring waters. British troops landed near the town on April 14, but their commander proceeded with excessive caution, and they did not force the Germans out of Narvik until May 28. By then the Norwegian campaign was almost over.
Anglo-French forces also landed at two small ports in the general area of Trondheim-Namsos 125 miles to the north on April 14 and Andalsnes 100 miles to the south three days later. They hoped to capture Trondheim and gain control of central Norway. But they launched this enterprise much too late and with a lamentable lack of planning. Although the Allies originally outnumbered the Germans in the Trondheim area by 13,000 to 2,000, they lacked heavy equipment, including artillery and tanks. The French found it particularly embarrassing when they had to leave most of their equipment aboard a cruiser that proved too long to penetrate into the small harbor at Namsos. The Allies were also well beyond the range of fighter planes based in Britain. The Germans, by contrast, used transport planes to reinforce their Trondheim garrison and provided strong tactical air support for their forces in the field.
Trondheim now became the key to Norway's fate. The Allies hoped to dislodge the German garrison by a pincers movement from north and south. It was not to be. They had to divert British forces from Andalsnes to aid hard-pressed Norwegian troops that were trying to prevent the Germans from penetrating up two narrow valleys toward Trondheim. But the British proved much too weak, and the Luftwaffe pounded the Allied troops mercilessly. Superior German strength forced them to fall back on Andalsnes. Meanwhile, Allied units pushing south from Namsos toward Trondheim made little progress due to the mountainous terrain and heavy snow cover. It proved necessary to evacuate all British and French troops from the two little ports early in May. Despite continued fighting in the Narvik area, the campaign was virtually over. The British finally abandoned Narvik early in June, and as they evacuated, a German naval force, including the battle cruisers Scharnhorst and Gneisenau, sank the aircraft carrier Glorious, two destroyers, and three merchant ships, sealing the Allied defeat.
The "ramshackle Norwegian campaign," as Churchill called it, had revealed woeful deficiencies in Allied strategic planning and tactical execution. German forces, in their first real engagement against the British and French, had out-thought, out-maneuvered, and out-fought their enemies. The entire Allied effort had been "too little, too late."
Germany had won another startling victory, adding to the developing myth of Wehrmacht invincibility. The triumph also secured concrete advantages for Germany. It removed any threat to the nation's northern flank and safeguarded access to Swedish iron ore. Germany had sealed off Sweden from the west, and the Swedes were in no position to be other than obliging suppliers of Germany's needs. In addition to iron ore, these included manufactured goods such as ball bearings as well as both warships and merchant vessels built in Swedish shipyards. The Reich also secured permission to use Swedish railroads to reinforce their stranded garrison at Narvik during the fighting in Norway and later to transport men and material eastward to take part in the Russian campaign. The conquest of Norway also provided bases from which German bombers, submarines, and surface raiders could attack British ships. Finally, it hampered the British naval blockade by greatly expanding the area that the Royal Navy had to patrol.
The campaign was not without its disadvantages for Germany, however. The German navy suffered serious losses, including the sinking of half of its 20 destroyers and three of its eight cruisers. In addition, Germany's two battle cruisers, and the pocket battleship Lutzow were disabled for months. Some observers have argued since the war that had these naval forces been available after the fall of France, they would have greatly enhanced German prospects for an invasion of Britain. But in view of Britain's continued naval supremacy and the threat posed by British air power, it is doubtful that the addition of these ships would have been a critical factor in enabling the Germans to cross the English Channel. Hitler also felt obliged to maintain a large defensive garrison in Norway. In the following years he increased its size markedly because of his persistent fear of an Allied invasion - an assault that never came.