Vyborg–Petrozavodsk offensive

Vyborg–Petrozavodsk Offensive
Part of World War II and the Continuation War
Date June 9 – August 9, 1944 Location Karelian Isthmus/East Karelia, Soviet Union Result Tactical stalemate, strategic Soviet victory
Belligerents
Finland Germany	Soviet Union
Commanders and leaders
C.G.E. Mannerheim Karl Lennart Oesch	Leonid Govorov Kirill Meretskov
Strength
75,000 soldiers initially 268,000 after reinforcements 1,930 guns 110 tanks 248 aircraft	450,000 soldiers 10,500 guns 800 tanks 1,600 aircraft
Casualties and losses
18,000 killed 45,000 wounded 3,000 captured

During World War II, in the Continuation War, the Vyborg–Petrozavodsk Offensive was a strategic offensive by the Leningrad and Karelian Fronts against Finland on the Karelian Isthmus and East Karelia fronts. The operation ended in stalemate. The Soviets captured most of East Karelia and Vyborg (Viipuri), and were also successful in drawing further German forces away from Army Group Centre, weakening the German position in Belorussia to some extent before the launch of Operation Bagration. However they did not achieve the objective of Kymi River and the destruction of the Finnish army. This was the largest operation in scope and scale ever fought in the Nordic countries.

The operations of each Front had their own limited operations

• Vyborg Offensive (9 June 1944 - 15 July 1944) by the Leningrad Front
• Svir–Petrozavodsk Offensive (21 June 1944 - 9 August 1944) Karelian Front

Background

In January 1944, Soviet forces had raised the Siege of Leningrad and driven the German Army Group North to the Narva-Lake Ilmen-Pskov line. Finland had queried for peace conditions in February, but the given conditions were considered impossible to fulfill. When the Finnish rejection became known and a breakthrough to the Baltic Sea was denied by the German resistance in Narva, the Stavka (Soviet Union's General Headquarters of armed forces) started to prepare for an offensive to force Finland's exit from the war on the side of Germany.

The plan

The Stavka plan called for a two-pronged offensive, one from Leningrad via Vyborg to the River Kymijoki, and the second across the Svir River through Petrozavodsk and Sortavala past the 1940 border, preparing for an advance deep into Finland. The plan called for the Finnish army to be destroyed in the Karelian Isthmus, and the remains blockaded against the western shore of Lake Ladoga between the two assaults and Lake Saimaa.

Finnish defensive positions. The Soviet offensive was stopped at the VKT-line.

The Finnish army had been preparing defensive fortifications since 1941, and on the Karelian Isthmus there were three lines of defence. The first two were the "Main line", which was constructed along the frontline of 1941, and the VT-line (Vammelsuu-Taipale) running 20 km behind the main line. These lines were reinforced with numerous concrete fortifications, but the work was still ongoing. The third line, the VKT-line (Viipuri-Kuparsaari-Taipale) was still on the drawing board and the construction of the fortifications began in late May 1944 at the Vyborg sector of the line. At the northern bank of the Svir the Finnish army had prepared a defence in depth area which was fortified with strong-points with concrete pillboxes, barbed wire, obstacles and trenches. Behind the 1940 border was after the Winter War built the Salpa Line with concrete bunkers in front of the River Kymijoki.

To overcome these obstacles, the Stavka assigned 11 divisions and 9 tank and assault gun regiments to the Leningrad Front. That meant that at the Isthmus there were 19 divisions, 2 division strength fortified regions, 2 tank brigades, 14 tank and assault gun regiments, all of which included over 220 artillery and rocket launcher batteries (almost 3,000 guns/launchers). Around 1,500 planes from the 13th Air Army and the Baltic Fleet naval aviation also contributed to the operation which included surface and naval infantry units of the Baltic Fleet.

To the East of Karelia, the Stavka planned to use 9 divisions, 2 sapper brigades, 2 tank brigades and 3 assault gun regiments, raising the whole strength to 16 divisions, 2 fortified regions, 5 separate rifle brigades, 2 tank brigades, 3 assault gun regiments and 3 tank battalions. They were supported by Lake Ladoga and Lake Onega naval flotillas and the 7th Air Army.

Vyborg Offensive

Soviet IS-2 destroyed in June 1944.

At the Karelian Isthmus front there were on average 120 Red Army artillery pieces for every kilometer, with up to 220 artillery pieces per kilometer on the breakthrough sector at Battle of Valkeasaari. The offensive opened with a huge aerial assault by the 1,600 strong 16th Air Army. The Finnish Army was in a strong position behind fortified positions, but the Soviet air attacks undermined resistance and many Finnish units retreated and suffered from thousands of desertions. On June 9, the Soviet offensive began, surprising the defending Finnish army. During the day, the Soviets captured frontline trenches and destroyed fortifications, so they were in good starting positions when the main thrust began at the morning of June 10, which shattered the Finnish defence at the breakthrough sector. Already, on June 13, the VT-line was reached and although it held out in the Battle of Siiranmäki, the defensive position was breached at Battle of Kuuterselkä on June 15.

The Finnish army tried to buy time by fighting delaying actions when retreating so that additional forces from East Karelia would reach the front, and the VKT-line could be prepared for combat. However, on June 19 the first Leningrad Front forces had reached Vyborg, and the first phase of the offensive was completed by the capture of the city on June 20, when defending Finnish 20th Infantry Brigade fled in panic.

Mannerheim had asked for German help, and on June 17 Gefechtsverband Kuhlmey arrived in Finland, followed on June 21 by the 303rd Assault Gun Brigade (at half strength) and the 122nd Infantry Division. Also, new German anti-tank weapons, Panzerfausts and Panzerschrecks, were issued to Finnish army troops. Late on June 21, German foreign minister von Ribbentrop arrived to Finland in an attempt to extract political consessions from the military help.

On June 22 the Finnish government asked for peace from the Soviet Union, but when the Soviet response arrived on the next day, it was interpreted by Linkomies as a demand for unconditional surrender, which it in reality wasn't. The Finnish misinterpretation of the Russian response was denied by the Soviet Union in an article published in Pravda on July 2, 1944.

On June 21, Stavka ordered continued attacks on the Imatra-Lappeenranta-Virojoki defence line, on the Salpaline sector of the front. Another group would attack northwards to Käkisalmi (now Priozersk, Russia) and surround the Finns defending the eastern VKT-line while preparations would be made for an advance towards Kotka, Kouvola and the Kymi river.

With Finnish army reinforcements, there were 268,000 Finnish army troops with 2,350 guns, 110 tanks/assault guns and 250 planes facing the two Red Army Fronts; 40% of the men and guns, and all the tanks were on the Isthmus. In all, the Red Army had a 6:5 advantage in men and 3-5:1 advantage in guns, planes and tanks against the Finnish army.

The offensive continued at June 25, when the Red Army breached the VKT-line at Tali, between the Bay of Vyborg and the Vuoksi river. At June 26 the Finnish president Ryti gave the guarantee to Ribbentrop that Finland would fight to the end alongside with Germany. In the ensuing battle, although the Leningrad Front managed to breach the VKT-line at Tali, but was bogged down at Ihantala, in the largest battle in Scandinavian history. When it became evident that a breakthrough was not possible at Ihantala, the Leningrad Front tried to double envelope the defenders with the twin assaults of the Bay of Vyborg and the Vuosalmi. However, the Finnish army was able to hold their positions on these sectors of the front.

At July 12 STAVKA ordered Leningrad front to release offensive elements from the Finnish front, and on July 15, the Red Army troops were ordered to assume a defensive posture, and offensive elements (mostly armour) were transferred to the German front for use in Operation Bagration.

Svir–Petrozavodsk Offensive

The Finnish Army had previously withdrawn most of its forces from the southern shore of the Svir River, so when the Red Army offensive started on 20 June, it did not achieve the desired surprise. The Karelian Front troops crossed the river the following day and secured a beachhead 8 km deep and 16 km wide. On June 23, a Northern Fleet naval infantry brigade attacked and captured a beachhead behind the Finnish lines between the Viteleenjoki and Tuuloksenjoki rivers, thus severing the main road along the shore of Lake Ladoga. Olonets was liberated on June 25, and on June 29, one of the main operation goals was achieved with the liberation of Petrozavodsk.

The Finnish Army retreated further, delaying the Karelian Front advance, allowing for the U-line, running northwards from Pitkäranta to Loimola and Kivijärvi, to be reinforced. The first Karelian Front units reached the U-line on July 10, but were fatigued following the long offensive, and failed to breach the defence line.

The last attempt to resume the offensive was made further north, where two Soviet divisions advanced towards Ilomantsi. Their attack was initially successful, and these divisions reached the border of 1940 on July 21, (the only Soviet units who did so in the offensive), but in the ensuing battle these divisions were surrounded and though they were able to escape from the encirclement back to east suffering heavy losses they were forced to leave their artillery and other heavy equipment behind.

Aftermath

The offensive succeeded in reclaiming East Karelia and driving the Finnish army to the northern side of the Bay of Vyborg and River Vuoksi. It also reopened the Kirov railroad and the White Sea Canal to Karelian Front forces.

However, the offensive failed to breach the VKT-line and Salpaline, and it did not succeed in destroying the Finnish army. Despite the losses suffered, the Finnish army was better equipped after the offensive than before, due to material delivered from Germany. The Soviets did not manage to surround units larger than a battalion in size, and even those managed to escape through forests by abandoning their heavy equipment. Soviet combat practice helped the Finnish army; the official history of IR 58 which fought against Red Army starting from Valkeasaari to Vyborg, notes that several times Finnish units were able to survive only because of the rigid adherence to operating area boundaries by the Soviet units, and inappropriate micromanagement by Red Army commanding officers.

The psychological effect of the offensive on the Finnish leadership should not be underestimated. Peace had to be achieved even under harsh terms. On the other hand, the Finns had stopped the offensive after only 100 km at the Karelian Isthmus, and the Battle of Ilomantsi had shown that Finnish army was still a viable fighting force. The only Stavka military solution to continued offensive would need fresh divisions from the reserve or the German front. To reach a conclusion to the conflict with Finland the Soviets made in June 1944 an ambiguous demand for a surrender which in Finland was interpreted as a demand for unconditional surrender and rejected. After the fighting had reached a stalemate in August 1944 another attempt was made to end the war. The Soviet Union offered in September 1944 an armistice with roughly the same treaty as in February 1944 though some of the demands were reduced, like the war reparations being halved and the time in which the reparations needed to be completed being extended.

References

• Bergstrom, Christer. (2007). Bagration to Berlin - The Final Air Battles in the East: 1944 - 1945, Ian Allen. ISBN 978-1-903223-91-8

Further reading

• S.P. Platonov: Bitva za Leningrad
• Ilya Moshansky: Sturm Karelskogo Vala. Vyborgsko-Petrozavodskaja strategicheskaja nastupatelnaja operazija 10 ijuna - 9 avgusta 1944 goda., "Vojennaja Letopis", BTV-MN, Moscow, 2005.