Benjamin B. Ferencz, born on 11 March 1920 in Transylvania (then part of Romania), was a lawyer and war crimes prosecutor best known for his role in the Nuremberg Trials after the Second World War. His family emigrated to the United States when he was still an infant, settling in New York, where he grew up in modest conditions. He later studied law at Harvard, where he developed an early interest in criminal law and the use of legal frameworks to address mass violence.

During World War II, Ferencz served in the United States Army. Toward the end of the conflict, he was assigned to a unit responsible for investigating Nazi crimes. As Allied forces advanced into Germany, he entered concentration camps and collected documentary evidence of atrocities, including reports detailing mass executions. These experiences shaped his understanding of the scale and organization of Nazi crimes and informed his later work as a prosecutor.

In 1947, at the age of 27, Ferencz became chief prosecutor in the Einsatzgruppen Trial, one of the subsequent Nuremberg proceedings. The case focused on mobile killing units that had carried out mass shootings in Eastern Europe, resulting in the deaths of over one million people, primarily Jews. Despite having no prior courtroom experience, Ferencz relied on captured German documents to demonstrate the systematic nature of the crimes. The trial led to multiple convictions and helped establish the legal basis for prosecuting crimes against humanity.

After the Nuremberg Trials, Ferencz remained involved in postwar justice efforts. He worked on compensation and restitution programs for victims of Nazi persecution and contributed to negotiations with German authorities and companies. Over the following decades, he became a consistent advocate for strengthening international law and preventing future atrocities.

Ferencz played a key role in promoting the creation of a permanent international criminal court. His long-term advocacy contributed to the establishment of the International Criminal Court (ICC) in 2002. Throughout his life, he argued that legal accountability should replace impunity in international affairs and that justice was essential to preventing future conflicts.

Ben Ferencz died on 7 April 2023 at the age of 103. He continued to speak publicly and engage with international justice initiatives well into his later years.