An American yesterday claimed to have unwittingly helped Hermann Goering to commit suicide and cheat the hangman at Nuremberg. The former soldier said he slipped Hitler’s number two a vial of cyanide.

For decades, historians have pondered how the art-loving war criminal managed to kill himself hours before he was supposed to be executed. One theory states that he hid the poison throughout his trial, another that Goering’s wife passed it to him in a kiss. Herbert Lee Stivers, a 78-year-old retired sheet-metal worker from southern California, has now volunteered a new explanation: He handed Goering the deadly capsule in the belief that it was medicine.

In 1946, Mr. Stivers was a 19-year-old private assigned to an honor guard that escorted defendants in and out of the courtroom. He told the Los Angeles Times he agreed to take the vial to the Nazi to impress a local girl, who called herself Mona.

She approached him in the street, was interested when he produced an autograph from another prisoner, Baldur von Schirach, and asked to keep it.

“The next day I guarded Goering and got his autograph and handed that to her,” Mr. Stivers told the newspaper. “She told me that she had a friend she wanted me to meet. The following day we went to his house.”

The woman introduced him to two men, apparently called Erich and Mathias. They told Mr. Stivers that Goering was “a very sick man” and needed medicine that prison officials were not providing.

Mr. Stivers, a member of the 1st Infantry Divison’s 26th Regiment, said he twice took notes from the men to Goering, concealed in a fountain pen. Then one of them gave him the capsule to deliver. “He [Erich] said it was medication, and that if it worked and Goering felt better, they’d send him some more,” Mr. Stivers recalled.

Two weeks later, hours before his execution on October 15, 1946, Goering committed suicide. In a note he claimed that he had the cyanide with him all along.

“I wasn’t thinking of suicide when I took it to Goering,” said Mr. Stivers, who was not interrogated by Army investigators after the death but was merely asked if he had seen anything suspicious. “He was never in a bad frame of mind. I would have never knowingly taken something in that I thought was going to be used to help someone cheat the gallows.”

A military investigation concluded that the commander in chief of the Nazi air force had the cyanide throughout his trial and hid it in “the cavity of the umbilical,” “in his alimentary tract,” and behind the rim of his cell lavatory.

But Mr. Stivers said he always doubted that. “I felt very bad after his suicide. I had a funny feeling; I didn’t think there was any way he could have hidden it on his body.”

Mr. Stivers, from Hesperia in San Bernardino County, said he had been haunted by the death but kept his involvement secret as he feared he could be charged by the military. It was only at the prompting of his daughter, Linda Dadey, that he agreed to speak out.

Her father felt he had “made peace with God” by coming forward, she said.

Many have questioned the Army version and suggested the poison was smuggled into the prison. In his 1984 book “The Mystery of Hermann Goering’s Suicide,” Ben Swearingen speculated that Lieutenant Jack Wheelis, who accepted a watch from Goering, allowed the Nazi to retrieve the vial from luggage kept in a prison storeroom.

Military records indicate that Mr. Stivers was a guard at the Nuremburg trials. His version of events cannot be proved but several experts said it had a ring of truth. However, Ann Tusa, the British historian who wrote the book “The Nuremberg Trials” with her husband John, said: “It’s possible but I would be cautious. There have been several people over the years who have come forward [to claim involvement].

“Nobody really knows. One questions this man’s motives, why he’s been so quiet so long. I’m just terribly puzzled why he should suddenly come forward.”