Vladimir Kren was a 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...

 of the Air Force of the Independent State of Croatia

Air Force of the Independent State of Croatia

The Air Force of the Independent State of Croatia, the Zrakoplovstvo Nezavisne Države Hrvatske was the national air force of the Independent State of Croatia during World War II, founded under German authority in April 1941...

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He held the rank of captain in the Yugoslav Royal Air Force

Yugoslav Royal Air Force

The Yugoslav Royal Air Force was formed in 1918 in the Kingdom of Serbs, Croats and Slovenes and existed until Yugoslavia's surrender to the Axis powers in 1941 following the Invasion of Yugoslavia during World War II....

 before defecting to the German army on January 4, 1941. With him he took plans of Yugoslav air fields, which he gave to German officials. On his return to the newly proclaimed Independent State of Croatia

Independent State of Croatia

The Independent State of Croatia was a World War II puppet state of Nazi Germany, established on a part of Axis-occupied Yugoslavia. The NDH was founded on 10 April 1941, after the invasion of Yugoslavia by the Axis powers. All of Bosnia and Herzegovina was annexed to NDH, together with some parts...

, he was named a colonel in the Croatian Home Guard

Croatian Home Guard

Croatian Home Guard or also, known as the "Homeland Defenders," was the name used for the armed forces of the Independent State of Croatia which existed during World War II.- Formation :...

. He was subsequently named the head of the air force on April 19, 1941.

He retired of his own request on September 13, 1943. However, he was brought back into service in June 1944, and remained until the state's defeat in 1945. In 1948 he was extradited to Yugoslavia

Yugoslavia

Yugoslavia refers to three political entities that existed successively on the western part of the Balkans during most of the 20th century....

 by the British, and was executed as traitor in Zagreb

Zagreb

Zagreb is the capital and the largest city of the Republic of Croatia. It is in the northwest of the country, along the Sava river, at the southern slopes of the Medvednica mountain. Zagreb lies at an elevation of approximately above sea level. According to the last official census, Zagreb's city...

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