Ukrainian-born Demjanjuk, a retired U.S. autoworker, has been denying the German prosecutor's charges from day one.
He maintains he was drafted into the Russian army in 1941, and later held by the Germans as a Soviet prisoner of war at German prison camps until 1944.
He says he's innocent of the charges against him, and claims he has never been to the Sobibor camp.
After the war, he found a job as truck driver in southern Germany, where his alleged SS past was never a problem, authorites have said.
He met his wife, Vera, there and the couple had their first child, daughter Lydia. The young family applied for permission to immigrate to America, where they arrived in January 1952.
Demjanjuk was granted U.S. citizenship in 1958. He moved his family to Ohio, where he began working for the Ford Motor Co. The couple had two other children, Irene and John Jr., and the family moved to a small house in the Cleveland suburb of Seven Hills, where they still live today.
Demjanjuk was sent to Israel, where he was convicted of being the notorious Nazi guard "Ivan the Terrible" at the Treblinka concentration camp in Poland.
He was found guilty in 1988 of war crimes and crimes against humanity, a conviction that was later overturned by the Israeli Supreme Court when new evidence showed another man was likely the Treblinka guard, allowing Demjanjuk to return to the United States a free man.
Demjanjuk's trial here, which could begin in the fall, will likely be Germany's last major Nazi trial.