Vyborg–Petrozavodsk offensive

1944 Soviet military offensive against Finland during the Continuation War

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The Vyborg–Petrozavodsk offensive or Karelian offensive was a strategic operation by the Soviet Leningrad and Karelian Fronts against Finland on the Karelian Isthmus and East Karelia fronts of the Continuation War, on the Eastern Front of World War II. The Soviet forces captured East Karelia and Vyborg/Viipuri. After that, however, the fighting reached a stalemate. The operations of the strategic offensive can be divided into the following offensives:
Viipuri (10–20 June) by the Leningrad Front
Virojoki Lappeenranta (21 June – 15 July) by the Leningrad Front
Koivisto landing (20–25 June) by the Baltic Fleet
Svir–Petrozavodsk (21 June – 9 August) by the Karelian Front
Tuloksa landing (23–27 June) by the Soviet Ladoga Flotilla

In January 1944, Soviet forces raised the Siege of Leningrad and drove the German Army Group North back to the Narva Lake Ilmen Pskov line. Finland had conducted peace negotiations intermittently during 1943–1944 with the Western Allies and the USSR, but no agreement had been reached. Finland asked for peace conditions again in February, but the Finnish Parliament (Eduskunta) considered the terms received impossible to fulfill. After Finland had rejected these peace conditions, and Germany halted the Soviet advance, the Stavka (Main Command of the Armed Forces of the Soviet Union) started to prepare for an offensive to force Finland's exit from the war.

In order to destroy the Finnish Army and to push Finland out of the war, the Stavka decided to conduct the Vyborg–Petrozavodsk offensive. The plan called for the Finnish army to be destroyed on the Karelian Isthmus, and the remains blocked against the western shore of Lake Ladoga between the two assaults and Lake Saimaa. The main strategic objectives of the offensive were to push Finnish forces away from the north of Leningrad, to drive Finland out of the war, and to create better conditions for a major offensive to the south against Germany. The Finnish army had been preparing defensive fortifications since 1940, and three lines of defence on the Karelian Isthmus. 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 River the Finnish army had prepared a defence in depth area which was fortified with strong points with concrete pillboxes, barbed wire, obstacles and trenches. After the Winter War, the Salpa Line was built behind the 1940 border with concrete bunkers in front of the Kymi river. To overcome these obstacles, the Stavka assigned 11 divisions and 9 tank and assault gun regiments to the Leningrad Front. That meant that there were 19 divisions, 2 division strength fortified regions, 2 tank brigades, 14 tank and assault gun regiments at the Isthmus, 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.

At the Karelian Isthmus front there were on average 120 Red Army artillery pieces for every kilometer of frontline, with up to 220 artillery pieces per kilometer on the breakthrough sector at Valkeasaari.

On June 10, the Soviet 21st Army, spearheaded by 30th Guards Corps, opened the offensive on the Valkeasaari sector, which was defended by 1st Infantry Regiment of Finnish 10th Division. During the day, the Soviet units captured frontline trenches and destroyed fortifications, shattering the first Finnish defense line at the breakthrough sector. was remembered, the government decided to interpret the Soviet response as a demand for unconditional surrender. It seemed that after Finnish unwillingness to accept the Soviet proposals in April 1944, owing to excessive reparation demands, Finland was to be offered only unconditional surrender. This was in line with Churchill's statement that as an Axis belligerent, Finland's surrender must be unconditional. The Soviet authorities denied this interpretation in an article published in Pravda on July 2, 1944, Furthermore, it is also known that at June 26 Stalin even told American ambassador Harriman that US diplomats could try to clarify to the Finns that he did not intend to take over the country. An unsigned draft document called "The Terms for Finnish Unconditional Surrender" was found in October 1993 in the Russian Foreign Ministry archive, which led some historians to conclude that unconditional surrender was indeed the Soviet goal. According to Baryshnikov this and similar drafts for the other countries the USSR was at war with existed since 1943, and they were replaced by new ones in the summer of 1944. With Finnish army reinforcements, there were 268,000 Finnish army troops with 2,350 guns (of which 1,030 field artillery, 393 heavy mortars), 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 total, the Red Army had a 1.7:1 advantage in men, 5.2:1 advantage in guns, and 6–7:1 advantage in planes and tanks against the Finnish army. However Finnish forces with 14 infantry divisions (a' 13,200), one armour division (9,200), 5 infantry brigades (a' 6,700), one cavalry regiment (4,300), 7 independent front border jaeger battalions, coastal defence forces and HQ/Corps artillery units even with full strength had less than 230,000 men. Less than 40 Finnish tanks and assault guns were modern (StuG III, T 34, KV 1) and less than 60 aircraft too (Bf 109 dayfighter and Ju 88 medium bomber). With these figures Red Army material advantage was about 1:20 at mid June 1944 (armour and aircraft). The Soviet troops tried to penetrate deep west after the Battle of Ihantala: in Äyräpää until July 18 and in Karelian Front even in early August. All offensives continued until very end – when there was no chance of a final decisive breakthrough. There hardly were any "limited objectives" on the Karelian Isthmus and Karelia. In the official history of the Great Patriotic War, failed offensives usually disappeared from memory as happened with the Vyborg–Petrozavodosk offensive. After Vyborg, the plan was to reach the Kymi river.

The Finnish Army retreated further, delaying the Karelian Front's advance, allowing for the U line, running northwards from Pitkäranta to Loimola and Kivijärvi, to be reinforced. The first 7th Army units reached the U line on July 10, but were fatigued following the long offensive and failed to breach the defence line. Soviet attempts to break through the U line at Nietjärvi ended with clear Soviet failure on July 17 when a Finnish counterattack regained the lost positions on the U line causing severe losses to the Soviet 114th Division. Once the attempts to gain breakthrough into the Finnish U line had failed Red Army attempted to go around the line by flanking it through the frontier north of the line. As Finns countered the flanking maneuvers the fighting extended far into the frontier in a makeshift extension of the U line however Soviet 7th Army managed neither to flank the extending Finnish line nor to break through it. Soviet losses in Nietjärvi were 7,000 KIA, MIA and WIA while Finnish forces lost 1,200 soldiers.

North of the U line the Soviet 32nd Army, which consisted of 176th, 289th, 313th and 368th Rifle Divisions, advanced after capturing Petrozavodsk towards small Finnish town of Ilomantsi while being delayed by defending Finnish 21st Brigade. Lack of suitable roads and the slow progress of 7th Army forced 32nd Army to move 313th and 368th Rifle Divisions to support 7th Army's offensive but they were blocked by the Finnish 1st Division. The Soviet attack towards Ilomantsi with the remaining 2 divisions (176th and 289th) was initially successful, and the divisions reached the border of 1940 on July 21, (the only Soviet units which did so in the offensive), but in the ensuing battle the divisions were surrounded and forced to escape the encirclement suffering heavy losses (est. 7,000 8,000 KIA, MIA, WIA if including losses of last week of July in Ilomantsi area ) and being forced to leave their artillery and other heavy equipment behind.

The offensive succeeded in reclaiming East Karelia and driving the Finnish army to the northern side of Viborg Bay and the Vuoksi River. It also reopened the original route of the Murman Railway and the White Sea Canal to the Karelian Front forces. as ordered by the Stavka. Despite the losses suffered, the Finnish army managed to avoid encirclement of battalion size units and benefited from supplies delivered by Germany. Based on documents found after 1991 in Russia the most important point of the plan the destruction of Finnish forces in Karelian Isthmus in a determined time and reaching a certain line (Kotka) had failed. Despite that, the psychological effect of the offensive on the Finnish leadership should not be underestimated. Even though the Finns had stopped the offensive at the Karelian Isthmus after 100 km and the Battle of Ilomantsi had shown that the Finnish army was still a viable fighting force, it was estimated that should the Soviet offensive continue at its full strength, the Finnish army would be able to last for three months at most. For Finland the overall situation required peace especially when Germans had not much chance to keep Finns on their side longer. This was probably in part brought about by international pressure exerted on the Soviets, especially by the U. S. and Britain. However, after the ceasefire the Soviets demanded that payments be based on 1938 prices which nearly doubled the actual amount to be paid,

In Soviet propaganda, this offensive was listed as one of Stalin's ten blows.