Nobel laureate Guenter Grass said on Tuesday his literary achievements were being denigrated following his belated admission that he had served in the Waffen SS during World War Two.
"What I'm experiencing is an attempt to make me persona non grata, to cast doubt about everything I did in my life after that," Grass said. "And that later life was marked by shame."
In an interview with ARD television ahead of the publication of his autobiography next month, the 78-year-old said his brief membership of the dreaded Waffen SS as a 17-year-old had influenced his life for the last six decades.
"I didn't do it and have to live with that," Grass said when asked why he had not revealed his guilty secret sooner.
"I'll certainly be hearing accusations about that for a long time. The only thing I can say is: I worked on that question in this book and everything I have to say about the matter is in it."
Grass, world-famous for his first novel The Tin Drum published in 1959 and an icon of the German left, made the shock admission in a newspaper interview on Saturday before the release of his autobiography Peeling Onions.
Grass has come under withering attack from writers, literary critics, historians and politicians over his confession. For decades, Grass had urged Germans to come to terms with their Nazi past.
Some have even called for Grass to be stripped of his Nobel literature prize, awarded in 1999. Former Poland president Lech Walesa demanded that Grass give up his honorary citizenship of Gdansk, the German's birthplace.
"Those who want to judge me will judge me," Grass said in an excerpts of a lengthy interview to be aired on Thursday.
German media reported on Tuesday that Grass's secret could have been revealed soon when East German Stasi security police files are opened.
Grass volunteered for submarine duty at 15 but was rejected. He was later called up to the Waffen SS aged 17 in the waning months of the war.
Grass had previously said he was drafted in 1944 to help anti-aircraft gun teams. He was held as a prisoner of war until 1946. After the war, he become an outspoken pacifist.
One of the most powerful organisations in Nazi Germany, the SS was first an elite force of volunteers that played a key role in the Holocaust, operating the death camps in which millions died. By the war's end, most were drafted and many were under 18.