Von Kleist, who was involved in 20 July 1944 plot and agreed to kill Nazi dictator with a suicide vest, has died aged 90.
Von Kleist, who once volunteered to wear a suicide vest to assassinate the Nazi dictator, died at his home in Munich on Friday, said his wife, Gundula.
Von Kleist was born on 10 July 1922, on his family estate Schmenzin in Pomerania, in an area of north-eastern Germany that is now part of Poland.
The Von Kleist family was a long line of Prussian landowners, who had served the state for centuries in high-ranking military and administrative positions.
Von Kleist's father, Ewald von Kleist, was an opponent of Hitler even before he came to power, and was arrested many times after the Nazi dictator took control in 1933. The elder Von Kleist famously travelled to England in 1938, the year before the second world war broke out, to try and determine whether other western nations would support a coup attempt against Hitler, but failed to get the British government to change its policy of appeasement.
Despite his family's opposition to the Nazis, the younger Von Kleist joined the German army in 1940, and was wounded in 1943 in fighting on the eastern front.
During his convalescence, he was approached in January 1944 by Colonel Claus von Stauffenberg, another officer from an aristocratic family, and presented with a plan to kill Hitler. Von Kleist had been chosen as the officer to model a new uniform for Hitler, and Von Stauffenberg proposed that he wear a suicide vest underneath, and detonate it when he stood next to the dictator.
Years later, Von Kleist remembered explaining the suicide plot to his father, who paused only briefly before telling his 22-year-old son: "Yes, you have to do this."
"Fathers love their sons and mine certainly did, and I had been quite sure he would say no," Von Kleist recalled. "But, as always, I had underestimated him."
The suicide attack plan never came to fruition.
Months later, however, Von Kleist was approached again by Von Stauffenberg to take part in what would become known as the 20 July plot – for the day in 1944 that the assassination was attempted – which was depicted in a 2008 film Valkyrie, starring Tom Cruise as Von Stauffenberg.
Von Kleist was supposed to play a key role as the person who was to carry a briefcase packed with explosives to a meeting with Hitler. In a change of plans, however, Von Stauffenberg decided to plant the bomb himself.
Von Stauffenberg placed the bomb in a conference room where Hitler was meeting with his aides and military advisers at his east Prussian headquarters. Hitler escaped the full force of the blast when someone moved the briefcase next to a table leg, deflecting much of the explosive force.
But when news spread that Hitler had survived, the plot crumbled and Von Stauffenberg, Von Kleist's father and scores of others were arrested and executed in an orgy of revenge killings. Some were hanged by the neck with piano wire. Von Stauffenberg was shot by firing squad.
Von Kleist himself was arrested and questioned at length by the Gestapo, and sent to a concentration camp, but then inexplicably let go and returned to combat duty.