In Denmark he used the pen name Sven Hazel.
Pedersen aka Hassel (or Hazel) was born on 19 April 1917 as the first of seven children to miller Peder Oluf Pedersen and his 20 year old wife Maren Hansine Andersen in Nyhuse, Frederiksborg Slotssogn in Frederiksborg County, Denmark and baptized Børge Willy Redsted Pedersen.
Pedersen aka Hassel claimed that at the age of 14 he joined the merchant navy as a cabin boy and worked on ships until his military service in 1936. However, while his two-years-younger brother Tommy Redsted Pedersen was entered in the army levy roll for Copenhagen in 1937 when he turned 18 (as number 403) and his four-years-younger brother Uffe Redsted Pedersen was entered in the same roll in 1939 when he turned 18 (as number 5035), Pedersen aka Hassel was not entered in the roll from 1935 through 1940.
In 1937, to escape the Great Depression, the unemployed Hassel moved to Germany to join the army. In an interview in 1990, he said, "Germany happened to be closer than England, I went to a Wehrmacht recruiting office to enlist, but it wasn't as easy as I had thought. Only German citizens could serve. After six months of trying to join up, the Seventh Cavalry Regiment finally accepted me on the condition that I became a naturalized German."
Hassel served with the 2nd Panzer Division stationed at Eisenach and in 1939 was a tank driver during the invasion of Poland. A year later he attempted to escape. He served with the 2nd Cavalry Regiment and later the 11th and 27th Panzer Regiments (6th Panzer Division) on all fronts except North Africa and was wounded several times. Eventually he reached the rank of lieutenant and received the Iron Cross 1st and 2nd class. He surrendered to Soviet troops in Berlin in 1945.
He claimed to have spent the following years in Prisoner-of-war camps in various countries but in reality he was arrested in Denmark in 1945 after the liberation and was held in prison there, first as a suspect and then as a convicted criminal.
On 6 January 1951 in Garrison Church, Copenhagen Pedersen aka Hassel married the four-years-older Laura Dorthea Guldbæk Jensen, a divorced film translator from Nørre Tranders. He registered his intent to marry as a journalist residing at Baggesensgade 1, Nørrebro. His best man was his younger brother Uffe Redsted Pedersen.
In 1952 his wife gave birth in St Josef's Hospital, Copenhagen, to a son, who was baptized Michael Franz Erwin Guldbæk Angouléme Arbing in Jesus Church, Valby. For the baptism he registered as a journalist and Lieutenant Colonel residing at Colbjørnsensgade 11 while his wife registered as Cand.mag.
He went to work in a car factory, but his wife encouraged him to continue to write about his experiences.
In 1953 his debut novel Legion of the Damned was published under the pen name Sven Hazel by Grafisk Forlag after their consultant Georgjedde (Georg Gjedde-Simonsen) had abbreviated and rewritten the manuscript. The same year he and his wife registered a phone as Lieutenant Colonel and Writer B. W. Arbing and Translator Laura Arbing at the address Hammelstrupvej 24, Copenhagen.
In 1957 Hassel suffered from an attack of a sickness caught during the war and was paralyzed for almost two years. After recovery, he began to write more books.
On 7 July 1961 he bought the property Stægers Alle 9, Frederiksberg under the name Børge Arbing and the following year he and his wife registered a new primary phone at that address under Dorthe & Willy Arbing.
In 1963 he reregistered the two telephones as Writer Sven Hazel with the second phone from then on at Grankogle Allé 10.
On 10 October 1963 journalist George Kringelbach revealed in his radio programme Natredaktionen on P3 that Sven Hazel was a pen name for the convicted traitor Børge Willy Redsted Pedersen. Hassel's publisher Grafisk Forlag subsequently offered all book dealers a refund for his most recent book and ceased collaboration with him. Pedersen aka Hassel therefore formed his own publishing company "Bellum" (Latin for 'War'), which published the remainder of his books.
On 29 September 1965 he changed his name to Sven Willy Hasse Arbing  and on 28 December 1965 he had his son's name changed to Michael Hasse Arbing while on 26 April 1966 his wife changed hers to Dorthe Laura Hazel Guldbæk Arbing nee Jensen.
On 15 August 1984 his wife sold her property Grankogle Allé 8, Greve to their son.
On 14 October 1986 he sold the property at Stægers Alle 9.
On 21 September 2012 he died, aged 95, in Barcelona.
Hassel's books are written in the first person, with Hassel himself as a character, though not necessarily the lead character. The books describe the exploits of a 27th (Penal) Panzer Regiment composed of expendable soldiers – sentenced criminals, court-martialed soldiers and political undesirables. In addition to Sven, they include Alfred Kalb, "Legionnaire" (ex-member of the French Foreign Legion); Wolfgang Creutzfeldt, a giant of a man ironically named Tiny (variously Little John in some of the books); barracks fixer and shrewd thief Joseph Porta; older sergeant Willie Beier, "Old Un" or "Old Man"; Julius Heide, an ex-Waffen SS NCO and Nazi fanatic, Barcelona Blom, a veteran of both sides of the Spanish Civil War, Gregor Martin, who was a removals man before the war, Chief Mechanic Wolf, and Staff Sergeant Hoffman, a non-commissioned officer. They serve on many fronts, including northern Finland, USSR, Italy (Monte Cassino), Greece (The Bloody Road to Death), the Balkans, and France (Liquidate Paris, set during and after the Normandy Invasion). The majority of the action occurs in the USSR. Due to errors in chronology, the regiment fights in several places, hundreds of kilometres apart, at the same time. In some of the books the 27th Regiment does guard duty for the Gestapo in Hamburg (Assignment Gestapo) and also at the military prison at Torgau (March Battalion). Hassel states that the characters are based on real people and events are related to historical events.
Hassel's view of war is brutal. In his books, soldiers fight only to survive, with the Geneva Convention rarely being observed on the Eastern front. People are killed by chance or with very little reason. Occasional pleasant events and peaceful meetings are brutally cut short. Unsympathetic Prussian officers constantly threaten their men with courts-martial and execute them with little provocation. Disgruntled soldiers occasionally kill their own officers to get rid of them. By graphically portraying war as violent and hopeless in such manner, Hassel's books have been said to contain an anti-war message.
Hassel's books are particularly popular in the United Kingdom, where he sold 15 million of the 53m sold worldwide.
The controversial Danish writer Erik Haaest has been disputing Hassel's claims for many years. Haaest writes that Sven Hassel is actually Børge Villy Redsted Pedersen (which was true until Hassel changed his name to Arbing in 1965). According to Haaest, the author never served on the Eastern front but spent the majority of World War II in occupied Denmark and his knowledge of warfare comes second-hand from Danish Waffen-SS veterans whom he met after the end of the war. Haaest claims that during the war period, Pedersen/Hassel was in fact a member of the HIPO Corps or Hilfspolizei, an auxiliary Danish police force created by the Gestapo, consisting of collaborators.
Haaest discovered that in 1945, after the liberation, Pedersen aka Hassel was arrested in Denmark and in 1947 tried and sentenced for collaboration with the Germans (Retsopgøret) and that therefore Pedersen/Hassel's claims that he spent the post-war years in various POW camps are not true.
Haaest also alleges that Pedersen/Hassel's first novel was ghostwritten and that, when it became a success, he employed his wife to write the rest of his books.
- The Legion of the Damned
- Wheels of Terror
- Comrades of War
- March Battalion
- Assignment Gestapo
- Monte Cassino (The Beast Regiment)
- Liquidate Paris
- Reign of Hell ISBN 0-304-36690-0
- The Bloody Road to Death
- Court Martial
- O.G.P.U. Prison
- The Commissar
- "Kulørt dansk krigsforfatter er død" (in Danish). Politiken. 2012-09-23. Retrieved 2014-09-24.
- "Kulørt dansk krigsforfatter er død" (in Danish). Jyllands-Posten. 2012-09-23. Retrieved 2014-09-24.
- Hillerød Parish Register (Birth) 1917-1921, p.3
- Valby Parish Register (Birth) 1950-1954, p.66
- Helligkors Parish Register (Birth) 1951-1952, p.268+351
- Tverstedvej 3-sttv, Copenhagen census 1930
- Vanløse Parish Register (Confirmation) 1928-1935, p.25
- Garnisionskirken Parish Register (Marriage) 1946-1961, p.119
- Mariakirken Parish Register (Marriage) 1944-1965, p.102
- "About the Author". 2014-03-28. Retrieved 2014-09-25.
- 1. Udskrivningskreds, Landrulle. Register til tilgangslister. 1. lægd (1848 - 1940)
- Rigsarkivet, Københavns Byret, 21. Afdeling for Retsopgørssager, Dombog 1945-1948, 8-46, Domsdato 12. November 1947
- "De fordømtes legion - Sven Hazel" (in Danish). Bibliotek.dk. Retrieved 2014-09-27.
- "Oplysninger om enkelte forfattere" (in Danish). 2014-07-31. Retrieved 2014-09-27.
- KTAS telefonbog [KTAS phone book] (PDF) (in Danish). Kjøbenhavns Telefon Aktieselskab. 1953. col. 490. "Arbing B W Oberstløjt. Forf. Hammelstrupv. 24 ... VA 3424 Y. Arbing Laura Transl. Hammelstrupvej 24 ... VA 3424 Y"
- KTAS telefonbog [KTAS phone book] (PDF) (in Danish). Kjøbenhavns Telefon Aktieselskab. 1957. col. 536. "Arbing Laura & Willie Hammelstrupvej 24 ... VA 4341. - Sommer ... NE: Hundige 69 Y"
- KTAS telefonbog [KTAS phone book] (PDF) (in Danish). Kjøbenhavns Telefon Aktieselskab. 1959. col. 514. "Arbing Laura & Willie Strindbergsvej 25 ... VA 4341. - Somm. Grankoglealle Hundige 150~ 12 90 01 50"
- KTAS telefonbog [KTAS phone book] (PDF) (in Danish). Kjøbenhavns Telefon Aktieselskab. 1960. col. 523. "Arbing Laura & Willie Strindbergsvej 25 ... VA 4341. - Somm. Grankoglealle 12 ... 90 01 50"
- Land register 18ap, 18aq, 18ar, Greve
- Land register 27bf, 27fø, Frederiksberg
- KTAS telefonbog [KTAS phone book] (PDF) (in Danish). Kjøbenhavns Telefon Aktieselskab. 1962. col. 545. "Arbing Dorthe & Willy Stægersalle 9 ... FA 7101. - Somm. Grankoglealle 12 Greve Strand ... 90 01 50"
- KTAS telefonbog [KTAS phone book] (PDF) (in Danish). Kjøbenhavns Telefon Aktieselskab. 1963. col. 2099. "Hazel Sven Forf. Stægersalle 9 ... FA 7101. - Somm. Grankoglealle 10 Greve Strand ... 90 01 50"
- KTAS telefonbog [KTAS phone book] (PDF) (in Danish). Kjøbenhavns Telefon Aktieselskab. 1964. col. 2162. "Hazel Sven Forf. Stægersalle 9 ... FA 7101. - Somm. Grankoglealle 10 Greve Strand ... 90 01 50"
- KTAS telefonbog [KTAS phone book] (PDF) (in Danish). Kjøbenhavns Telefon Aktieselskab. 1965. col. 2220. "Hazel Sven Forf. Stægersalle ... 11 FA 7101. - Somm. Grankoglealle 10 Greve Strand ... 90 01 50"
- Vejgaard parish register 1905-1914 (birth), p.308
- "Publishers & Agents". 2014-09-28. Retrieved 2014-03-28.
- "svenhassel.net Whois Lookup & IP". 2014-09-25. Retrieved 2014-09-25.
- SS General (Cassell Military Paperbacks). "Brutality of the Second World War". Amazon.com. Retrieved 2012-07-06.
- Wheels of Terror / The Misfit Brigade in the covershut website
- "Sven Hassel obituary". The Guardian. 2 October 2012. Retrieved 17 March 2014.
- "Erik Haaest challenging Hassel's claims". Home.tiscali.dk. Retrieved 2012-07-06.
- "Books by the author". Librarything.com. 1917-04-19. Retrieved 2012-07-06.
- Official website
- Paul, Vitello, "Sven Hassel, Novelist Who Depicted Nazi Soldiers’ Lives, Dies at 95," New York Times, October 6, 2012.