Pfefferberg was born into a Jewish family in Kraków, Austro-Hungarian Empire. He gained a master's degree in philosophy and physical education from the Jagiellonian University, Kraków. He then became a high-school teacher in Kraków until 1939. He became the physical education professor at Kosciuszko Gymnasium in Podgórze.
In 1939 he joined the Polish Army and took part in the defense of Poland against the German invasion. He later explained to the Australian novelist Thomas Keneally how he was wounded on the San River where his life was saved by his sergeant major, who carried him to a field hospital.
In 1941 he married Ludmila "Mila" Page (née Lewison) with whom he later had two children. Mila was herself a survivor of the Kraków-Płaszów concentration camp. During the making of the movie Schindler's List, she was introduced to Ralph Fiennes who was in full costume as Amon Göth, the role in which he was cast. On seeing him, Mila began to uncontrollably shake, feeling as if she were seeing Amon Göth himself.
Also see Oskar Schindler
After the defeat of Poland and its partition between Nazi Germany and the Soviet Union, Pfefferberg needed to decide to travel East or West. In his own words:
"We officers had to decide to go east or west. I decided not to go east, even though I was Jewish. If I had, I would have been shot with all the other poor sons of bitches in Katyn Forest."
As a prisoner at Płaszów, near Kraków, Pfefferberg used a German-issued document to visit his soldiers in a military hospital, and also to visit his mother. In this way he met Oskar Schindler, a Sudeten-German businessman who was taking over an enamelware factory that had been confiscated from Jews. Schindler employed Pfefferberg's mother, an interior designer, to decorate his new apartment.
Through this connection Pfefferberg was employed in Schindler's factory near the Kraków-Płaszów concentration camp outside Kraków. This enabled him to survive the extermination of 3 million Polish Jews, during which his parents, sister, brother-in-law and many other relatives were murdered. Pfefferberg described Schindler as "a modern Noah," who was able to save a number of Kraków Jews from deportation to the nearby extermination camp at Auschwitz. Those he saved became known as Schindlerjuden or "Schindler's Jews".
He moved with Schindler and many others to a camp at Brünnlitz. During these experiences he acquired skill as a welder.
After the war Pfefferberg settled first in Budapest, then in Munich where he organized a school for refugee children. In 1948 he emigrated to the United States. He and his wife settled in Los Angeles in 1950, eventually opening a leather goods business in Beverly Hills. In the United States he used the name Leopold Page, although in later years he apparently reverted to Pfefferberg. He tried on a number of occasions to interest the screenwriters and film-makers he met through his business in a film based on the story of Schindler and his actions in saving Polish Jews from the Nazis, arranging several interviews with Schindler for American television. Schindler's death in 1974 seemed to end any possibility of a film.
In 1980 when Thomas Keneally went into Pfefferberg's shop to ask about the price of briefcases, Pfefferberg learned that Keneally was a novelist and showed him his extensive files on Schindler. Keneally was interested, and Pfefferberg became an advisor for the book, accompanying Keneally to Poland where they visited Kraków and the sites associated with the Schindler story. Keneally dedicated Schindler's Ark to Pfefferberg: "who by zeal and persistence caused this book to be written."
Pfefferberg explained the reasons behind his efforts to have the Schindler story told as:
"Schindler gave me my life, and I tried to give him immortality."
After the publication of Schindler's Ark in 1982, Pfefferberg worked to persuade Steven Spielberg to film Keneally's book, using his acquaintance with Spielberg's mother to gain access. Pfefferberg claimed to have called Spielberg's office every week for 11 years. When in 1992 Spielberg agreed to make the film, Pfefferberg worked as an advisor, again making the trip to Poland to show Spielberg the sites; he appears in the film's epilogue and is listed in the end credits as a consultant, under the name Leopold Page. Pfefferberg and his wife were Spielberg's guests on the night Schindler's List won seven Academy Awards. In his acceptance speech Spielberg thanked "a survivor named Poldek Pfefferberg ... I owe him such a debt. He has carried the story of Oskar Schindler to all of us."
Pfefferberg was a founder of the Oskar Schindler Humanities Foundation, which recognises acts by individuals and organizations, regardless of race or nationality. He remarked on the Foundation:
"Only when the foundation is a reality will I say I have fulfilled my obligation. Because when I am no longer here, when the Schindler Jews are not here, the foundation will still go on."
Pfefferberg died on March 9, 2001, aged 87, in Beverly Hills.
In April 2009 a carbon copy of the original list (including 801 names) was found in Sydney among the documentation Thomas Keneally gave as a donation to the State Library of New South Wales.