It had been ceded to the Soviet Union on 13 March 1940, in the Moscow Peace Treaty, which marked the end of the Winter War.

The main task to break through the Soviet defences between Värtsilä and Korpiselkä was given to VI Corps, commanded by Maj. Gen. Paavo Talvela.

After clearing the resistance the 11th Division advanced and rounded the southern end of the Jänisjärvi Lake and set up positions facing west along the Jänisjoki River.

[5] Simultaneously, the Finnish VII Corps had been attacking southwards on the west side of Jänisjärvi Lake; however, strong Soviet defensive effort turned the offensive into a crawl.

Its advance tied down some Soviet troops, but Talvela who commanded the Finnish VI Corps assessed that Group Oinonen's mission had been a resounding failure.

[7] The main Finnish advance continued southwards towards the town of Loimola (ru), through which ran the railroad between Sortavala and Petrozavodsk.

General Talvela pressed his forces further and the 1st Jaegar Brigade finished its 110 km long contested advance when it reached the shore of Lake Ladoga at Koirinoja (ru) the next day.

After the VI Corps reached the 1939 border on July 23 Mannerheim ordered a halt the next day to advances further east and set the forces to preparing defensive positions along the Tuulema River.