On March 12, 1940, a peace treaty was signed with Finland, which ended the Soviet-Finnish war and ensured an advantageous change of borders
The Soviet-Finnish war of 1939-40 is not considered successful in our history. Indeed, at a superficial glance, it seems that this is precisely a failure - after all, the big USSR was not able to capture all of "small" Finland (although the country of Suomi in the pre-war borders was, for example, larger than Germany).
The Soviet-Finnish war, which began in November 1939, actually became the third armed conflict between Finnish nationalists and the Soviet regime - the first two took place during the civil war and at the very beginning of the 1920s. At the same time, the extreme Finnish nationalists who seized power in the former “Grand Duchy of Finland” in 1918 with the help of the troops of the German Kaiser were not only anti-communists, but most of them were ardent Russophobes, hostile to any Russia in principle.
It is not surprising that in the 20-30s of the last century, the authorities in Helsinki not only actively prepared for a war against the USSR, but also quite openly proclaimed their goals aimed at tearing away all the "Finno-Ugric territories" from our country from Karelia and up to to the Urals. Another thing is surprising today - most of the representatives of the Finnish government in the 30s not only prepared for war with us, but also hoped to win it! The Soviet Union of those years was considered by the Finnish nationalists to be weak, internally fragmented due to the recent enmity between the "whites" and the "reds" and the obvious difficulties of life due to collectivization and forced industrialization.
Knowing the internal politics and ideology that prevailed in Finland before World War II, there is no doubt that without the Soviet-Finnish war of 1939-40, the Helsinki authorities would have gone on a "campaign against communism" together with Hitler, as did, for example, the authorities Hungary, Slovakia, Croatia and Italy (with which the USSR never fought at all).
The Kremlin was well aware of such sentiments of its Finnish neighbors. At the same time, the situation was extremely complicated by the configuration of the Soviet-Finnish border. During the years of our civil war, taking advantage of the temporary weakness of Soviet Russia, the Finnish nationalists not only seized part of Karelia and the city of Vyborg (where they staged a massacre of the Russian population, including even those who supported not the Bolsheviks, but the "whites"), but also pushed the Finnish border close to the city of Petrograd.
Until November 1939, the state border passed several kilometers from the city limits of modern St. Petersburg, long-range artillery from the territory of Finland could then shell the city of Leningrad. With such a border line in winter, our Baltic Fleet became defenseless - locked in ice in Kronstadt, it could be captured even by a simple offensive of the infantry, which needed to pass only 10 km on the ice from the territory that was then under the Finns.
Photo: wiki2.org
On the eve of World War II, the Kremlin did not doubt that the hostile Finnish authorities would participate in any coalition war against our country, be it the Anglo-French or German coalition. And the Finnish border, close to Leningrad, meant that in the event of such a war, the USSR immediately loses over 30% of its scientific and industrial potential, concentrated in the city on the Neva.
Therefore, back in 1938, the Soviet Union offered the Finnish authorities a defensive treaty, which excluded the possibility of using Finnish territory by third countries for actions against the USSR. The months-long negotiations in Helsinki ended with the refusal of the Finnish side. Then an exchange of territories was proposed - for sections of the Karelian Isthmus, several islands in the Gulf of Finland and the Barents Sea, the Finnish side was offered twice as large territory in Soviet Karelia. The Finnish authorities rejected all proposals - England and France promised them assistance against the USSR, at the same time the Finnish generals communicated more and more closely with the German General Staff.
A month and a half before the start of the Soviet-Finnish war, on October 10, 1939, general mobilization began in Finland. Our Leningrad military district was also preparing for a possible collision. In parallel, in October-November, there were intense diplomatic negotiations with the Finnish delegation in Moscow.
The Soviet-Finnish war itself lasted just over three months - from the morning of November 30, 1939 to noon on March 13, 1940. At the same time, it is usually forgotten that from the side of the USSR, the war was initially started by inexperienced units of the Leningrad district, while the best Soviet troops at that time were either in the Far East, where only in September 1939 the big battles with the Japanese ended, or left for the new western border of the Soviet Union, to the newly annexed lands of Western Belarus and Galicia.
Faced with the setbacks of the first month of fighting, when our army buried itself in the impenetrable snow-covered forests and serious fortifications of the "Mannerheim Line", the Soviet authorities managed to do a lot of work in just one second month of the war. More trained units and new types of weapons were transferred to the "Finnish front". And already in the third month of the war, in February 1940, our troops stormed numerous Finnish bunkers and ground the main forces of the Finnish army.
Therefore, on March 7, 1940, a delegation from Helsinki urgently flew to Moscow for new peace talks, where they understood perfectly well that their possibilities for independent resistance were almost exhausted. But Stalin's government also feared that because of the protracted war, the risk of intervention by Britain and France on the side of the Finns increased. The authorities of London and Paris, being formally in a state of war with Germany, did not conduct real hostilities against Hitler in those months, but they quite openly threatened war on the Soviet Union - in France they had already begun to prepare an expeditionary force to help Finland, and the British concentrated in Iraq, then their colonies, their long-range bombers for a raid on Baku and other cities of the Soviet Caucasus.
As a result, both the Finns and the Soviet Union agreed to a compromise peace, signed in Moscow on March 12, 1940. On the part of the USSR, the treaty was signed by the People's Commissar (Minister) of Foreign Affairs Vyacheslav Molotov, the head of Soviet Leningrad, Andrei Zhdanov, and the representative of the General Staff of our army, Alexander Vasilevsky.
Under this treaty, the hostile Finnish border was moved 130 kilometers west of Leningrad. The USSR inherited the entire Karelian Isthmus, including the city of Vyborg, annexed to Russia by Peter I. Ladoga became our internal lake, and by pushing the border to the north, in Lapland, the Soviet Union secured the only railway to Murmansk. The Finns pledged to lease the Hanko Peninsula and the sea area around it for the Baltic Fleet base - taking into account the new bases in Estonia (which will become part of the USSR in the summer of 1940), the Gulf of Finland, in fact, turned into the inland sea of our country.
We can say directly that it was the Moscow Treaty of March 12, 1940 that saved Leningrad and the entire north-west of Russia from being captured by the Nazis and Finns in the next 1941. The border pushed to the west did not allow the enemy to immediately reach the streets of the city on the Neva, and thus in the first days of the war deprive our country of a third of its military industry. Thus, the treaty on March 12, 1940 was one of the first steps towards the Great Victory on May 9, 1945.