Leon was born in 1926 in Łódź and later deported to the Litzmannstadt Ghetto. He survived multiple concentration camps, including Auschwitz-Birkenau, Gross-Rosen, Flossenbürg, and Natzweiler-Struthof. Leon returned to Poland after the war pursuing a career as a medical doctor until he was expelled in 1968. He resettled in Sweden and continued his medical career. In 2022, Leon published the book “Reconciliation with Evil: Story of a Survival”. At the age of 97, he continues to be a powerful advocate for education as a means of preventing such atrocities from happening again.