Citat:
In the inter-war decades, the town, then officially known as Viipuri, was the second biggest town in Finland and the seat of Viipuri Province. In 1939, Vyborg had some 80,000 inhabitants, including sizable minorities of Swedes, Germans, Russians, Gypsies, Tatars, and Jews. During this time, Alvar Aalto built the Vyborg Library—a masterpiece of modern architecture.
During the Winter War between the Soviet Union and Finland in 1939–1940, over seventy thousand people were evacuated from Vyborg to western Finland. The Winter War was concluded by the Moscow Peace Treaty, which stipulated the transfer of Vyborg and the whole Karelian Isthmus—emptied of their residents—to Soviet control, where it was incorporated into the Karelo-Finnish Soviet Socialist Republic on March 31, 1940. As the town was still held by the Finns, the remaining Finnish population, some ten thousand people, had to be evacuated in haste before the handover. Thus, practically the whole population of Finnish Vyborg was resettled elsewhere in Finland. The town became the administrative center of Vyborgsky District.
The evacuees from Finnish Karelia came to be a vociferous political force and their wish to return to their homes was an important motive when Finland sought support from Nazi Germany against the Soviet threat. As a result, Finland and Nazi Germany fought on the same side in the Continuation War.
On August 29, 1941, Vyborg was recaptured by Finnish troops and, soon after, the Government of Finland formally annexed it along with the other areas lost in the Moscow Peace Treaty. At first, the Finnish Army did not allow civilians into the town. Of the 6,287 buildings, 3,807 had been destroyed. The first civilians started to arrive at the end of September and by the end of the year Vyborg had a population of about 9,700. By 1942, it had risen to 16,000. About 70% of the evacuees from Finnish Karelia returned after the re-conquest to rebuild their looted homes, but were again evacuated after the Red Army's Vyborg–Petrozavodsk Offensive, timed to coincide with the Battle of Normandy. By the time of the Soviet offensive, the town had a population of nearly 28,000. The town was evacuated by June 19 and the defense of Vyborg was entrusted to the 20th Brigade. The town fell to the Red Army on June 20, 1944, but the Finns managed to halt the Soviet offensive at the Battle of Tali-Ihantala—the largest battle fought by any of the Nordic countries—in Viipuri rural municipality which surrounded the town. The town was seriously damaged, with many historic buildings, including the Vyborg Cathedral, destroyed.
In the subsequent Moscow Armistice of September 19, 1944, Finland returned to the borders set by the Moscow Peace Treaty and ceded more land than the treaty originally demanded. In the 1947 Paris Peace treaties, Finland relinquished all claims to Viipuri/Vyborg.
After the Winter War, Leningrad Oblast wanted to incorporate the area of Vyborg, but it took until November 1944 for it to be finally transferred from the Karelo-Finnish SSR.[15] During the Soviet era, the town was settled by people from all over the Soviet Union. The naval air bases of Pribilovo and Veshchevo were built nearby.