In the Second World War, there had been even worse massacres, of course, considering the sheer number of casualties. There was the Holocaust, above all. And yet, the Fosse Ardeatine mass killing, carried out in Rome on March 24, 1944, commands special attention. It stands out not only for the cruel execution of so many innocent victims — mostly civilians, some of them very young — but also because there is something mysterious and inexplicable surrounding its details, even if we attempt to assume as our standpoint the evil rationality of the killers. It was not an act of war. It was pure terrorism.

The Ardeatine tragedy took place at a time of utter chaos. Italy had entered the war as an ally to Germany; the fascist leader Benito Mussolini originally had been a master and an inspiration for Adolf Hitler. But in 1943, Italy was losing the war on many fronts. The Allies landed in Sicily, and Rome was bombed for the first time. King Victor Emmanuel III, as head of the government and commander of the armed forces, ordered the arrest of Mussolini and appointed marshal Pietro Badoglio to head a new military government. Badoglio at first pretended to continue fighting as an ally to Germany, even as he was secretly negotiating a surrender with the Allies.

The Germans, anticipating an Italian defection, started moving more troops into Italy. Badoglio signed an unconditional surrender on Sept. 8. The king and his family, Badoglio, and the entire government fled to southern Italy, far from the reach of the Germans. Their choice to switch alliances was inevitable, and long overdue. But the manner in which it was implemented was cowardly, a betrayal of the people of Italy and its soldiers. The government abandoned most of the Italian territory and population to utter chaos, and to the revenge of the German army and special police, the SS. The Italian army was left without leaders and without orders, and many of its soldiers were arrested and deported to concentration camps. Some Italian officers enrolled in the armed partisan resistance, which began to strike German forces. (In the Italian language afterward, the “Eight of September” became a metaphor for desperate anarchy.)

Rome was supposed to be an “open city,” a demilitarized zone, but, in fact, it was occupied by the German military. One of its battalions, the Bozen regiment, was mobilized to suppress the resistance. Its members were ethnic Germans from the northern Italian province of Alto Adige, or South Tyrol. The Bozen regiment used to march through downtown Rome daily, singing. On March 23, 1944, on the anniversary of the foundation of the Fascist Party, a group of partisans hid a bomb inside a rubbish cart along the path of the Bozen regiment. It exploded, killing 32 soldiers and two civilian bystanders, including an 11-year-old boy.

The chief of the SS in Rome, Herbert Kappler, and the commander of the German armed forces, Gen. Kurt Maelzer, immediately decided there should be a reprisal: 10 Italians must die for each German killed. (Adolf Hitler was overruled: he had asked for a reprisal ratio of 50 to 1).

But this is where the tragedy doubles with a mystery. The German commanders didn’t attempt to apprehend the partisans who killed their soldiers. They didn’t issue the order that those responsible for the attacks should surrender or else cause innocent civilians to die in their place. The German commanders didn’t even announce that a reprisal was in the making. They decided instead that everything should happen quickly, that the execution must take place within 24 hours and under the utmost secrecy. During the night between March 23 and 24, they gathered 271 prisoners already in jail, indicted for crimes that were often political. They added 57 Jews, just because they were Jews. The chief of the fascist police offered some Italians from his prison. In the end, there were 335 victims. Even the arithmetic was flawed.

The technique of the execution was exceptional, too, for its speed and its secrecy. The German commanders didn’t want any witnesses. They selected a distant quarry on the outskirts of Rome, in an area surrounded by catacombs. The prisoners were transported there on trucks. Their execution should require a minimum amount of ammunition. They were escorted, five by five, from the trucks to the quarry, with their arms tied behind their backs. Once there, they were forced to kneel so that their executioners could shoot them in the back of the head, at the base of the skull. With only a single bullet allocated per each prisoner shot, none were wasted. The German executioners had to aim very precisely at their targets. The space inside the quarry was narrow, so while the executions proceeded, the new victims had to climb over the still-warm bodies of the previous ones. At the end, there was a mountain of corpses.

This was butchery, not the job for traditional soldiers. The Bozen regiment had refused to participate. Even for the SS special police it was unusual. They were used to torturing their prisoners, not killing them by the dozens, individually, “manually.” Their officers had to provide the executioners with the available drugs: schnapps, brandy. By getting drunk, they became sloppy. Some victims — this was discovered when they were finally exhumed and autopsied — were only wounded at first; they tried to crawl away, and died later. Only in one case was a corpse found without his hands tied. He was a boy, 15 years old, executed together with his grandfather. They were hugging each other when they died. Also among the victims was a priest, Don Pietro Pappagallo, who later became the inspiration for a character in Roma, città aperta (“Rome, Open City”), Roberto Rossellini’s film.

In the end, the German SS were themselves covered in blood. They had to drink more alcohol, to get drunker and drunker, and to try and forget. Then the SS commanders attempted to hide the corpses. They had garbage dumped, hoping that the dirt would cover the stench of death, and blew up the entrance to the caves. In that area permeated with ancient history, one of the first to discover the massacre was a monk, a custodian of the nearby San Callisto Catacombs. More than two months later, little by little, the pilgrimage from Rome began, and the truth was revealed. But vermin had taken a terrible toll, and many corpses were disfigured to the point that relatives could not recognize them. Some were identified only a decade ago, with DNA testing.

What could possibly explain this massacre, which even the very executioners wished to hide, even though its magnitude was of their own choosing? The judicial truth, established when some SS chiefs were tried for war crimes, is partial and unsatisfactory. The German commanders in 1944 felt that they were losing the war, and this made them even crueler. Their troops were a small minority in Rome, surrounded by a mostly hostile population. They probably felt that by openly announcing a reprisal, or even giving publicity to the attack in Via Rasella, they could trigger an uprising. They behaved like terrorists. And yet they were somehow effective, at least in the short term. The partisan attacks decreased dramatically and came almost to an end inside Rome.

The Holy City was liberated by the Allies on June 4.

You can visit the Mausoleum of the Fosse Ardeatine, where all the victims have been buried; it’s a 20-minute ride from the center of Rome. William Schuman did.

Federico Rampini is a journalist and a writer, based in New York City. He is the U.S. bureau chief of the Italian daily newspaper La Repubblica.

Note: In collaboration with the Consulate General of Italy and the Italian Cultural Institute of in Chicago, the Chicago Symphony Orchestra will present special programming in remembrance of the Fosse Adreatine massacre. The Italian Cultural Institute in Chicago, 500 N. Michigan, Suite 1450, hosts Federico Rampini for a book signing of his book, When Our History Began, on Wednesday, Feb. 20, at 6 p.m. The event is free, but registration is required. In addition, Rampini will join Anthony Cardoza, professor of history at Loyola University, for a special pre-concert conversation at Orchestra Hall on the Armour Stage at 6:15 p.m. on Feb. 21. A special exhibit on the Adreatine massacre will be on display on the first floor of the Symphony Center Rotunda Feb. 18-23. This exhibit is presented by the University of Rome, “Tor Vergata,” Department of History, Cultural Heritage, Education and Society.

TOP: Fosse Ardeatine (1950) by Renato Guttuso from his series of works made for the 30th anniversary of the massacre, now in the collection of the Fosse Ardeatine Mausoleum.