And one in six youngsters said they thought Auschwitz was a Second World War theme park while one in 20 said the Holocaust was a celebration at the end of the war.
The survey for a veterans’ charity also found one in 10 thought the SS stood for Enid Blyton’s Secret Seven, and one in 12 believed the Blitz was a European clean-up operation following the Second World War.
Scottish-based charity Erskine, which provides nursing and medical care for veterans, said it would now take part in a nationwide scheme to educate schoolchildren about the two world conflicts.
The charity questioned 2,000 children between the ages of nine and 15 about their knowledge of the key people and events of the two wars.
While a quarter admitted they did not think about the soldiers who died in the conflicts, and 40% said they did not know when Remembrance Day was, 70% of all those surveyed said they wanted to learn more about the two wars in school.
Major Jim Panton, chief executive of Erskine, said: “Some of the answers to this poll have shocked us and it has shown that Erskine, amongst others, has a part to play, not just in caring for veterans but in educating society as a whole.
“As we approach Remembrance Day it is hard to believe that 40% of our children do not know when it is.”