David, a former postal worker himself, started collecting postcards and stamps sent from the concentration camps five years ago.

"I found this era of postal history fascinating.

"As a union member I could have been sent for slave labour. I discovered that even Masons were persecuted," he said.

David has letters to loved ones from the Lodz ghetto and Thereisenstadt and even from Auschwitz.

He has a 1940 telegram signed by Auschwitz Commandant Rudolf Hoss addressed to the parents of a Polish political prisoner informing them that their son was dead. Jewish victims were given no such courtesy.

David has collected Nazi propaganda material at trade fairs. He has postcards from the 'Eternal Jew Exhibition' held in Vienna and Munich in 1937. One poster described the Jew as an "infidel and revolutionary Marxist".

Another poster from 1942 warned German men of the dangers of tainting Aryan blood by marrying Jewish women.

Money coupons issued in the Lodz and Warsaw ghettos give a glimpse of the parody of normal life that existed there.

One hundred Kronen notes issued in Thereisenstadt concentration camp depict Moses and the Ten Commandments.

A letter addressed from prisoner Liese Dragon to a relative in Richard Wagner Strasse 34, bears a Star of David postage stamp.

David also owns a yellow star worn by Dutch Jews like Anne Frank.

David said: "I hope the exhibition makes people think, 'How did this happen?'"