The IV Corps was a formation of the Finnish Army during the Winter War

Winter War

The Winter War was a military conflict between the Soviet Union and Finland. It began with a Soviet offensive on 30 November 1939 – three months after the start of World War II and the Soviet invasion of Poland – and ended on 13 March 1940 with the Moscow Peace Treaty...

 against the Soviet Union

Soviet Union

The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

. It defended the area north of Lake Ladoga

Lake Ladoga

Lake Ladoga is a freshwater lake located in the Republic of Karelia and Leningrad Oblast in northwestern Russia, not far from Saint Petersburg. It is the largest lake in Europe, and the 14th largest lake by area in the world.-Geography:...

 against Soviet attacks. It was commanded by Major General

Major General

Major general or major-general is a military rank used in many countries. It is derived from the older rank of sergeant major general. A major general is a high-ranking officer, normally subordinate to the rank of lieutenant general and senior to the ranks of brigadier and brigadier general...

 Juho Heiskanen

Juho Heiskanen

Juho Henrik Heiskanen was a Finnish Major General during the World War II.Heiskanen joined the Jaeger Movement in 1915 and trained and fought in the Royal Prussian 27th Jäger Battalion. In 1916, he was arrested by Gendarmerie in Jyväskylä and sent to Petrograd...

 and from 4 December 1939 by Major General Woldemar Hägglund

Woldemar Hägglund

Johan Woldemar Hägglund was a Major General in the Finnish Army in the Second World War, and an early volunteer in the Finnish Jäger troops in Finnish Civil War 1918.- Early years :...

. The IV Corps defeated superior Soviet troops by using motti tactics.

Order of battle

• 12th Division (12.D) led by Lauri Tiainen
  Lauri Tiainen
  Lauri Taavetti Tiainen was a Finnish Colonel during the World War II.Tiainen joined the Jaeger Movement in 1915 and trained and fought in the Royal Prussian 27th Jäger Battalion. He worked under the name "Pfadfinder"...
  
  
• 13th Division (13.D) led by Hannu Hannuksela
  Hannu Hannuksela
  Hannu Esa Hannuksela was a Finnish Major General during World War II.Hannuksela joined the Jaeger Movement in 1916 and trained and fought in the Royal Prussian 27th Jäger Battalion. He served in a jaeger artillery during the Finnish Civil War...
  
  
• Separate Battalion 8 (Er.P.8)
• Separate Battalion 9 (Er.P.9)
• Separate Bicycle Company 4 (Er.PPK 4)

Also attached to the corps was Group Talvela commanded by Commander

Commander

Commander is a naval rank which is also sometimes used as a military title depending on the individual customs of a given military service. Commander is also used as a rank or title in some organizations outside of the armed forces, particularly in police and law enforcement.-Commander as a naval...

 Paavo Talvela

Paavo Talvela

Paavo Talvela was a Finnish soldier and a Knight of the Mannerheim Cross. He was one of the volunteers who served in the Finnish Jaeger battalion in Germany in 1916 to 1917. He was a battalion commander in the Finnish Civil War...

. Group Talvela covered the IV Corps northern flank up to the forces of the North Karelian Group

North Karelian Group

The North Karelian Group was a formation of the Finnish Army during the Winter War. It defended the wide stretch of border between the Finnish IV Corps and the troops around Suomussalmi...

. Group Talvela defeated a Soviet Division in the Battle of Tolvajärvi

Battle of Tolvajärvi

The Battle of Tolvajärvi ['tol.va.jær.vi] was fought on 12 December 1939 between Finland and the Soviet Union. It was the first large offensive victory for the Finns in the Winter War.-Prelude:...

, one of the first Finnish victories of the war. Group Talvelas order of battle:

• Infantry Regiment 16 (JR 16)
• One battalion of the replacement brigade (XII/KT-Pr)
• Separate Battalion 11 (Er.P.11)
• Separate Battalion 112 (Er.P.112)
• Bicycle Battalion 7 (PPP 7)
• two artillery batteries (9.Ptri/KTR 13 and 5.Ptri/KTR 12)