Karl Hass (5 October 1912 – 21 April 2004) was an SS officer and German spy who helped deport more than 1,000 Italian Jews to Auschwitz. A perpetrator in the Ardeatine massacre, in which 335 civilians were murdered, he was tried and convicted in Italy in 1998. He spent the last years of his life under limited house arrest in "the splendor of the beautiful Swiss Alps".
Hass was born in Kiel. In 1934, Hass joined the Sicherheitsdienst (SD), the SS's intelligence service, where his ruthlessness brought promotion. After the downfall of Benito Mussolini and the occupation of Italy by Nazi Germany, Karl Hass was sent to Rome to set up a network of radio operators and to organize saboteurs behind the invading Allied lines. While in Rome, serving under SS-Obersturmbannführer Herbert Kappler, Karl Hass aided in the deportation of more than 1,000 Jews to Auschwitz.
Hass was also the officer who had Princess Mafalda of Savoy, the daughter of King Vittorio Emanuele III of Italy, placed into German military custody, which eventually resulted in her death. He reputedly lured her to his headquarters in Rome by the suggestion that there was a message from her husband who was then being held in Berlin. On her arrival at the German command, Hass had the princess arrested and sent for questioning to Munich in Germany. She was subsequently sent to Berlin and then to Buchenwald concentration camp, where she was later wounded in an Allied bombing raid. Despite receiving medical attention at the camp, she died following an operation to amputate her infected arm.
Following a 23 March 1944 bomb attack in the Via Rasella by Italian resistance fighters that killed 33 soldiers, Hass, Capt. Erich Priebke and fellow officers rounded up 335 Italians and the next day transported them to the Ardeatine caves at the outskirts of Rome. Hass, Priebke, and their soldiers systematically executed each captive with a shot to the back of the head. The Ardeatine massacre is one of the most notorious in the Italian history of World War II.
After the war, SS-Hauptsturmführer Hass was taken prisoner by the Allies, but rather than being brought to justice for his war crimes, he was apparently employed by the United States Army Counter Intelligence Corps to spy on the Soviet Union. Only Kappler was charged with the Ardeatine cave massacre. In the early 1990s, Priebke, who had helped Hass with the executions, was interviewed in Argentina by an American television crew and as a result of the ensuing uproar in Italy was eventually extradited to stand trial. Hass returned to Italy to testify against Priebke. However, on the night before he was due to testify, Hass decided against testifying against his old colleague, and attempted to flee from his hotel room by climbing down from an outside balcony. He seriously injured himself after slipping and falling from the balcony and was taken to hospital where he ultimately gave testimony to Court officials. In the court records, Hass admitted the execution of two civilians, but defended his actions by claiming he was only following orders, a defense which has been ruled invalid ever since the Nuremberg trials.
Tried and convicted for his role in the Ardeatine action, he was sentenced to life in prison in 1998. Considered to be in poor health, Hass was held under limited house arrest in what was described as "a retirement villa in his favorite area of Switzerland" until his death in 2004.