# Operation B (1945–1947)

The Operation B was a name for Czechoslovak military operation aimed against members of Ukrainian Insurgent Army who entered Czechoslovak territory.

## Prelude

UPA was tasked with conducting raids into Czechoslovak territory. In particular, the goal was to analyze internal political situation of Czechoslovakia. UPA leadership believed that "Bolshevization" of Czechoslovakia was proceeding more slowly than in other Eastern states, so it was the best place to spread OUN propaganda. In September 1945, UPA fighters tasked with the raids were given training, in particular "to strengthen political education work in the departments raiding foreign lands". On 8 August, 1945, insurgents completed their final preparations for the raid. Czechoslovak authorities responded with Operation "B" when UPA incursions into Czechoslovakia begun.

## Operation

First members of Ukrainian Insurgent Army entered Czechoslovakia on 13 August, 1945, near the villages of Spišská Stará Ves and Medzilaborce. There were reports of other groups attacking robbing villages near border with Poland. Czechoslovakia sent more units to the area that pushed Ukrainian insurgents back to Poland. Czechoslovak units were commanded by Colonel Jan Heřman.
Polish army launched offensive against Ukrainian Insurgent Army in January 1946. Czechoslovakia reacted by sending more units near borders expecting more insurgents trying to enter Czechoslovakia. Ukrainian Insurgent Army became more active near Polish border with Slovakia and more units entered Czechoslovak territory there. In April 1946 units led by Colonel Heřman launched offensive against insurgents pushing them back to Poland. During late 1946, situation in Slovakia became calmer.
During early 1947, insurgents led some raids to Czechoslovak territory and during summer 1947 launched their largest attack to Czechoslovakia trying to reach western Europe through its territory. Some groups even entered Moravia and South Bohemia. The bloodiest clash occurred on 5 August, 1947, at Partizánská Ľupča which resulted in death of 6 members of Czechoslovak security forces. Czechoslovak units were gradually destroying Ukrainian insurgents, and fights concluded on 17 November, 1947, when the last forces of the Ukrainian Insurgent Army were pushed out. Members of OUN captured 33 villages in Czechoslovakia.

## Aftermath

The operation resulted in heavy losses for UPA. Despite this, some insurgents crossed to the West and accomplished objectives of their raid. UPA and OUN members who lost contact with command continued crossing to the West. Stepan Bandera estimated that around 300 UPA fighters and OUN members crossed into West Germany during 1947–1949. UPA losses were claimed to have been 3 times higher than Czechoslovak ones. Other sources put UPA losses at 61 killed and 289 captured. Estimates of UPA losing 80–85% of their force were given. However, these could be overstated figures and do not correlate with the number of insurgents that crossed to the West, combined with the fact that insurgents broke into smaller units in order to cross to the West, making accurate calculations more difficult. Regardless, UPA's daring raid was rejoiced and seen as a great success.

## Popular culture

1951 Czechoslovak film Operation B focuses on Czechoslovaks participating in military operations against Ukrainian Insurgent Army.
1975 episode of Thirty Cases of Major Zeman called Ruby Crosses was inspired by Ukrainian Insurgent Army activities in Czechoslovakia.
The 1978 film Shadows of a Hot Summer focuses on a family taken hostage by Ukrainian Insurgent Army.
The 1984 film Pasáček z doliny depicts members of Ukrainian Insurgent Army who entered Czechoslovakia.