The Expedition
The expedition crossed the border on the night of April 21 1919. The goals were to capture Lotinanpelto, Petrozavodsk and the Murmansk railroad. The troops was divided into three groups and were made up of a 1000 volunteers. The souther group advanced to Lotinanpelto in just three days, but was pressed back behind River Tuulos by Bolshevik troops. The norhtern group captured Prääsä. At this time it became obvious that there wasn't enough troops to complete the goals of the expedition. A new round of recruiting 2000 new volunteers was started and Mannerheim made Aarne Sihvo the new commander of the expedition.
Major Paavo Talvelas regiment started an attack aimed at Petrozavodsk on June 20, but was beaten by Bolsheviks and Finnish Red Guard forces just outside the town. The English troops that operated along the Murmansk railroad were quite close by, but did not participate.
The Finns had hoped that the Karelian population would have joined the troops as volunteers but only a few did and their morale was never very high.
The initiative now passed to the Bolsheviks. On June 26 over 600 Finns of the Red Officer School in St. Petersburg made a landing at Vitele across Lake Ladoga behind the Finnish lines. The southern group was forced to retreat to Finland after suffering heavy losses. Talvelas group was also forced to retreat back to Finland.
Aftermath
The only result from the expedition was that the parish of Porajärvi declared on June 6 that it wished to join Finland. As had the parish of Repola already done in 1918. The regular Finnish Army moved in to occupy the parish. In the treaty of Tartu in 1920 Finland and Soviet Union agreed on their common border. Repola and Porajärvi were left on the Soviet side and the Finnish troops had to be withdrawn before February 14 1921. The young police chief in Repola, Bobi Sivénin shot himself in protest.