Astounding: How Finland Held off an Invasion From the Mighty Soviet Union

By Balcer~commonswiki - Own work, CC BY 2.5,
April 2, 2020 Topic: History Region: Europe Blog Brand: The Buzz Tags: Winter WarFinlandSoviet UnionWorld War IIMilitaryTechnology

Astounding: How Finland Held off an Invasion From the Mighty Soviet Union


North of Ladoga-Karelia, the roads became scarcer and the forest even more impenetrable. Only a handful of rough paths traversed the central part of Finland, although communications improved as one proceeded west. What passed for roads in the country’s midsection were so far apart that Russian forces moving on parallel routes could not support one another. Worse, the poor roads could not handle heavy traffic and barely managed to support the movements of single Russian divisions traveling along them.

The most important objective for the Russians was the capture of the town of Viipuri at the northwestern corner of the isthmus. With the town’s vital road network in hand, the Soviets would have an easy pathway by which to penetrate into the populated western and northern portions of Finland. Soviet strategy for the prosecution of the war was to advance along the entire Finnish border in overwhelming strength, pushing the enemy hard from eight different directions by means of a coordinated westward advance. This would allow the Russians to hammer the Mannerheim Line from both front and rear. In the north, the plan was for the Murmansk-based Fourteenth Army (three mediocre infantry divisions with attached armor) to occupy the Lapland port of Petsamo and take the town of Oulu on the Gulf of Bothnia. With that accomplished, much of the aid coming to the Finns from Sweden would be blocked.

The midsection of Finland was to be attacked by Ninth Army, five rifle divisions along with a motley assortment of armored units, which would move westward to take as many of the Finns’ communications centers as possible, thus cutting the country in two. In the Ladoga-Karelia sector, the Russian objective was to turn the northern flank of the isthmus’s defenses by circling around Lake Ladoga’s north shore and striking the Mannerheim Line from behind. This vital task was assigned to the Russian Eighth Army, which comprised six rifle divisions and two tank brigades. Facing the Karelian Isthmus was the Russian Seventh Army, made up of 14 infantry divisions, three armored brigades, and a mechanized corps containing over 1,000 tanks. Supporting these units were considerable artillery assets. This force was to breach the Mannerheim Line by frontal assault, take the city of Viipuri, and sweep west toward the Finnish capital of Helsinki.

In overall operational control of the Soviet forces at the start of the war was Lt. Gen. Kirill Meretskov, commander of the Leningrad Military District since 1938. Having distinguished himself during the Russian Civil War, the chubby, non-professionally trained soldier had survived Stalin’s purges and was noted for diligence, if not inspired leadership. He estimated that the struggle with Finland would be concluded in 12 days.

A Responsive Finnish Strategy

The Finns’ strategy was one of wait and see. They guessed correctly about the size and scope of their enemy’s thrust up the Karelian Isthmus and at Suomussalmi in the central part of the country and prepared well to counter the attacks. But they underestimated the power of the Soviet attack on the Karelia-Ladoga axis, which was undermanned by friendly forces. The end game for the Finns was to hold on until the West came to their rescue or Stalin settled for a negotiated peace. Barring those results, the Finns were determined to fight to the last man.

On the eve of war, the Finns established a covering force stretching 625 miles from the Arctic Ocean southward toward the north shore of Lake Ladoga, with Civic Guard and reservists under Lt. Gen. Viljo Tuompo. From the north bank of Lake Ladoga and extending 60 miles farther north was Maj. Gen. Woldemar Hagglund’s 4th Corps, consisting of two infantry divisions. On the western side of the Karelian Isthmus stood the Finnish II Corps under Lt. Gen. Harald Ohquist, with three infantry divisions and advance troops operating forward of the Mannerheim Line. To the east, connecting with Lake Ladoga’s southern shore, were two divisions of the III Corps’s two infantry divisions and one detachment of covering troops. Overall command of the III and  IV Corps was exerted by General Hugo V. Ostermann of the Army of the Karelian Isthmus.

Slowing the Russian Advance

On November 30, Russian air raids on Helsinki, Viipuri, and other Finnish cities and towns heralded the start of the Winter War. That same day, Soviet landing parties from the Baltic Fleet occupied several key Finnish islands in the Gulf of Finland. The next day, Meretskov stormed across the frontier with 120,000 men, 1,000 tanks, and 600 artillery pieces. From the start, Russian columns experienced massive traffic jams caused by the poor road conditions, snowstorms, and token Finnish resistance, which reduced the Russian advance to a crawl or immobilized it completely.

Prior to the Russian attack, the Finns had evacuated much of the population in the border area and conducted a scorched-earth policy to deprive the enemy of both shelter and sustenance. Hundreds of booby traps delayed the Russians and caused many casualties. Single Finnish snipers were able to halt large Soviet forces for hours. Because the Russians were sticking to the few good roads, their formations were bunching up, preventing them from properly deploying for battle. As a result, the separate columns were unable to support one another and were exposed to Finnish flank attacks.

At the outset of the war, the biggest threat to the Finns was the Russians’ tanks. The defenders had few antitank weapons and little training in using them. Although Russian tank tactics were crude, straight-ahead charges, they proved effective in driving the Finns back from the border to the Mannerheim Line during the first days of the war. But by the end of the first week, the Finns had discovered ways to counter the enemy armor: logs and crowbars jammed into the wheels of the steel monsters, Molotov cocktails (gasoline- and chloride potassium-filled bottles), and bunches of stick grenades or satchel charges placed on tank treads all proved effective armor killers. Eighty Russian tanks were destroyed by such methods during the border fighting. Although as many as 70 percent of the tank-busting squads became casualties, there was never a lack of volunteers for the extremely hazardous, close-quarter duty.

Defending the Mannerheim Line

By December 6, the Finns had withdrawn to the Mannerheim Line, a series of 109 reinforced concrete positions covering 80 miles. Fronting the line were vast fields of barbed-wire entanglements, thousands of mines planted on all likely avenues of approach, and five to seven rows of granite rocks sunk into the ground to serve as antitank obstacles. The line’s principal weakness was the fact that its pillboxes were too far apart to provide mutual fire support for each other. More critical was that the Finns did not have enough artillery or ammunition to support the line. Regardless, when defended by stubborn troops and attacked by poorly led Russian soldiers not properly supported by artillery or tanks, the Mannerheim Line proved formidable and effective.

Throughout most of December, the Russians attacked the Mannerheim Line, first on the left flank near the town of Taipale, then at Summa on the right. The fighting assumed a familiar pattern: the Russians would unleash a heavy artillery barrage, followed by frontal attacks by infantry and small groups of tanks that followed the tightly packed infantry column in the open. Deliberate and carefully laid down Finnish artillery and machine-gun fire (the latter at extremely close range) would come into play, plastering the Russians as they struggled through minefields and barbed wire and sending the Soviets into headlong flight.

By December 20, the first Soviet offensive on the Karelian Isthmus had failed. Seven infantry divisions and two armored brigades supported by 600 guns and 1,000 planes had not made a dent in the Mannerheim Line. The cost to the Russians was enormous—thousands killed, many more wounded or unable to function in the bitter winter conditions that even the Soviets were not equipped to contend with. More than 250 Russian tanks were destroyed.

The Finnish Counterattack

On December 23, the Finnish high command launched a counterattack from the Mannerheim Line. Lack of fresh troops and blasting snow storms coupled with fierce enemy resistance brought the attack to a halt that same day. The Finns lost 1,300 battle casualties in return for a few miles of ground gained. North of Lake Ladoga, in the Finnish IV Corps sector, the start of the war saw significant gains by the Russian 155th, 139th, and 168th Infantry Divisions on the left of the corps near the town of Suojarvi and southward to Lake Ladoga’s northern shore. The Finns had not anticipated the strength of the enemy attack in the area, leaving the section badly undermanned. The weak Finnish covering force was pushed back for five days until Mannerheim sent the 6th and 9th Divisions to the threatened sector to prevent the vital communication center of Tolvajarvi from falling.

Stinging small-unit raids, followed by larger battalion-sized attacks, enabled the Finns to stop the Russian advance north of Lake Ladoga. Confined to the few roads in the area because of deep snow and hampered by severe cold and lack of food and proper clothing, the demoralized Soviet forces were surrounded by the Finns in the foreboding forests. Pressured by their unseen enemy, the Soviets tried to retreat or hunkered down in the snowy waste to be surrounded and mopped up by the Finns. The battle for Tolvajarvi cost Finland 630 killed and 1,320 wounded. The Russians sustained 5,000 killed, 5,000 wounded, and 600 taken prisoner. Fifty-nine tanks and armored cars were destroyed. The victory at Tolvajarvi secured Finland’s northern flank for the rest of the war.