Związek Odwetu was a Polish

Poland

Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

 World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 resistance organization established on April 20, 1940. It was created by Gen. Stefan Rowecki

Stefan Rowecki

Stefan Paweł Rowecki was a Polish general, journalist and the leader of the Armia Krajowa. He was murdered by the Gestapo in prison, probably on the direct order of Heinrich Himmler.-Life:Rowecki was born in Piotrków Trybunalski...

, the head of the Związek Walki Zbrojnej

Zwiazek Walki Zbrojnej

Związek Walki Zbrojnej was an underground army formed in Poland following its invasion in September 1939 by Germany and the Soviet Union that opened World War II.The precursor to the ZWZ was the Service...

, as the branch of that organization focused on sabotage

Sabotage

Sabotage is a deliberate action aimed at weakening another entity through subversion, obstruction, disruption, or destruction. In a workplace setting, sabotage is the conscious withdrawal of efficiency generally directed at causing some change in workplace conditions. One who engages in sabotage is...

 and diversion.

Early history

The ZO was formed out of a variety of previously-existent sabotage groups which were then merged into the ZWZ. Initially a part of the ZWZ, all of them were then separated. Thus the risk of eliminating the whole ZWZ by destruction of one of its sabotage cells was eliminated.

Initially headed by Maj. Franciszek Niepokólczycki

Franciszek Niepokólczycki

Franciszek Niepokólczycki - colonel and a sapper in the Polish Army, soldier of the Polish Home Army and the anti-communist organization Freedom and Independence and a political prisoner during the Stalinist period in Poland.From November 1918 on he was a member of Polish...

 Teodor, the organization was aimed at diminishing the German military and industrial potential by means of active and passive sabotage. It also carried out a number of revenge actions as a reprisal for particularly brutal German mass shootings, łapankas or other actions aimed at Polish civilians. The net of sabotage and intelligence cells organized by the ZO included almost every major German-controlled factory in occupied Poland, as well as a number of special detachments, used by the ZO's headquarters for particularly difficult actions.

Increased resistance measures

In February 1942, the commander in chief of the Polish forces and the prime minister of Poland, Gen. Władysław Sikorski, withdrew his order of limiting armed resistance in Poland, the ZO's network started to grow significantly. It also organized a number of spectacular actions against the German war effort. Out of several hundred thousand actions (mainly in Silesia

Silesia

Silesia is a historical region of Central Europe located mostly in Poland, with smaller parts also in the Czech Republic, and Germany.Silesia is rich in mineral and natural resources, and includes several important industrial areas. Silesia's largest city and historical capital is Wrocław...

, Lesser Poland

Lesser Poland

Lesser Poland is one of the historical regions of Poland, with its capital in the city of Kraków. It forms the southeastern corner of the country, and should not be confused with the modern Lesser Poland Voivodeship, which covers only a small, southern part of Lesser Poland...

, Holy Cross Mountains and Mazovia

Mazovia

Mazovia or Masovia is a geographical, historical and cultural region in east-central Poland. It is also a voivodeship in Poland.Its historic capital is Płock, which was the medieval residence of first Dukes of Masovia...

), perhaps the best known is the Wieniec

Wieniec

Wieniec is a village located in Lesser Poland, Poland....

. During that action, carried out in October 1942, the Polish resistance blew up all railways leading from and to Warsaw, destroyed 4 German supply trains going for the Eastern Front and disrupted the supply transport for several days (with the Warsaw train hub being cut out for roughly 15 hours). In December, the action was continued by the ZO in Eastern Poland, as a reprisal for the German terror in the area around Zamość

Zamosc

Zamość ukr. Замостя is a town in southeastern Poland with 66,633 inhabitants , situated in the south-western part of Lublin Voivodeship , about from Lublin, from Warsaw and from the border with Ukraine...

.

Merger into Armia Krajowa

After the ZWZ was reformed into the Armia Krajowa

Armia Krajowa

The Armia Krajowa , or Home Army, was the dominant Polish resistance movement in World War II German-occupied Poland. It was formed in February 1942 from the Związek Walki Zbrojnej . Over the next two years, it absorbed most other Polish underground forces...

, the ZO was again incorporated into it, merged with the Wachlarz

Wachlarz

Wachlarz |folding fan]]) was a Polish World War II resistance organization formed by the Armia Krajowa for sabotage duties behind the German Eastern Front, outside of the Polish borders. Its commanders were Lt.Col. Jan Włodarkiewicz and Lt.Col...

 and Osa

Osa

Osa may refer to:*Osa peninsula, a peninsula in Costa Rica*Osa, Allahabad, a village in Allahabad, India*Osa, Warmian-Masurian Voivodeship *Osa, Russia, name of several inhabited localities in Russia*Osa class missile boat...

 units and formed the backbone of the Kedyw

Kedyw

Kedyw , was an underground movement - Armia Krajowa organization during World War II, which specialized in active and passive sabotage, propaganda and armed action against Nazi German forces and collaborators.-Operations:...

 organization. During the later stages of its existence, the ZO was headed by Maj. Jan Wojciech Kiwerski.