After Ben graduated from Harvard Law School in 1943, he joined an anti-aircraft artillery battalion preparing for the invasion of France. As an enlisted man under General Patton, he fought in most of the major campaigns in Europe. As Nazi atrocities were uncovered, he was transferred to a newly created War Crimes Branch of the Army to gather evidence of Nazi brutality and apprehend the criminals.

In his 1988 book, Planethood, Ferencz writes: “Indelibly seared into my memory are the scenes I witnessed while liberating these centers of death and destruction. Camps like Buchenwald, Mauthausen, and Dachau are vividly imprinted in my mind's eye. Even today, when I close my eyes, I witness a deadly vision I can never forget-the crematoria aglow with the fire of burning flesh, the mounds of emaciated corpses stacked like cordwood waiting to be burned.... I had peered into Hell.” Munich, 1945

A Post-War Mission

On the day after Christmas 1945, Ferencz was honorably discharged from the U.S. Army with the rank of Sergeant of Infantry. He returned to New York and prepared to practice law. Shortly thereafter, he was recruited for the Nuremberg war crimes trials. The International Military Tribunal prosecution against German Field Marshal, Herman Goering and other leading Nazis was already in progress under the leadership the American Prosecutor, Robert M. Jackson on leave from the US Supreme Court. The U.S. had decided to prosecute a broad cross section of Nazi criminals once the trial against Goering and his henchmen was over.

General Telford Taylor was assigned as Chief of Counsel for 12 subsequent trials. Ferencz was sent with about fifty researchers to Berlin to scour Nazi offices and archives. In their hands lay overwhelming evidence of Nazi genocide by German doctors, lawyers, judges, generals, industrialists, and others who played leading roles in organizing or perpetrating Nazi brutalities. Without pity or remorse, the SS murder squads killed every Jewish man, woman, and child they could lay their hands on. Gypsies, communist functionaries, and Soviet intellectuals suffered the same fate. It was tabulated that over a million persons were deliberately murdered by these special “action groups,” or Einsatzgruppen.

Ferencz became Chief Prosecutor for the United States in The Einsatzgruppen Case, which the Associated Press called “the biggest murder trial in history.” Twenty-two defendants were charged with murdering over a million people. He was only twenty-seven years old. It was his first case.

All of the defendants were convicted. Thirteen were sentenced to death. The verdict was hailed as a great success for the prosecution. Ferencz’s primary objective had been to establish a legal precedent that would encourage a more humane and secure world in the future.

 Growing Interest In International Law

According to Ferencz, “Nuremberg taught me that creating a world of tolerance and compassion would be a long and arduous task. And I also learned that if we did not devote ourselves to developing effective world law, the same cruel mentality that made the Holocaust possible might one day destroy the entire human race.”

In 1970, with the United States sinking ever deeper into the quagmire of Vietnam, it was only natural that his mind should turn to the need for a peaceful world. After careful deliberation, Ferencz decided that he would gradually withdraw from the private practice of law and would dedicate himself to studying and writing about world peace.

 Towards An International Criminal Court

Ferencz’s book Defining International Aggression-The Search for World Peace was published in 1975. It seemed to him that there was little sense in denouncing aggression, terrorism, and other crimes against humanity unless these offenses became part of an accepted international criminal code enforced by an international court. Ferencz published another two-volume documentary history, An International Criminal Court-A Step Toward World Peace, which was intended to be a tool that nations could use to build a structure for peace.

While still at Harvard, Ferencz had studied jurisprudence with Professor Roscoe Pound, one of the most learned jurists in the world. The results of his research were recorded in another two-volume book, Enforcing International Law-A Way to World Peace, which was published in 1983. In order to spread the word to a larger audience, he condensed the gist of his thinking into a small, inexpensive paperback, A Common Sense Guide to World Peace, the title influenced by that great patriot, Tom Paine, whose pamphlet Common Sense had inspired the American Revolution.

In 1988 Ferencz wrote Planethood with Ken Keyes, Jr. to offer practical steps for the average citizen to take to help establish international law and urge U.N. reform. Receiving critical acclaim from its readers, with over 450,000 copies printed and served as an inexpensive and easy-to-read “Key to Survival and Prosperity.”

With the coming of the 1990s and the end of the Cold War, the international community finally proved ready to discuss seriously the possibility of establishing an international criminal court, and Ferencz remained a voice of optimism. When the Rome Statute was affirmed by vote in 1998, Ferencz addressed the Conference asserting that “an international criminal court - the missing link in the world legal order - is within our grasp.” Since Rome, Ferencz has been active at Preparatory Commission sessions for the ICC, monitoring and making available his expertise on current efforts to define aggression. Ferencz has continued to mobilize support for the ICC, take on media punditries and inform an oft-misinformed media about the ICC. With the progress that has been made since Rome, Ferencz’s goal of replacing the “rule of force with the rule of law” seems imminent.

He lives in Florida. With his wife Gertrude, who died in 2019, Ben has four grown children. He continues to write and speak worldwide for international law and global peace.