A Berlin court found Krenz, 60, guilty of manslaughter for four killings during the 1980s at the barrier that divided the city between 1961 and 1989. Even though Krenz did not pull the trigger, the court said the successor to Erich Honecker was none the less guilty because he shaped the shoot- to-kill orders that were carried out by border guards who shot at least 263 people. "I won't give up!" Krenz called when a supporter in the back of the courtroom shouted "All the best, Egon!"
There was a gasp in the courtroom from a large group of old-guard Communist supporters when judge Josef Hoch ordered Krenz detained immediately - unusual for a German court - because he said there was a danger he would try to flee.
Krenz, who had denounced the trial as "victors' justice", was taken to the adjoining Moabit prison, a mile west of where the Wall once stood.
Two other former members of East Germany's Politburo, Guenter Schabowski and Guenther Kleiber, were found guilty of manslaughter for three killings at the Wall. They received terms of three years but were set free until the verdicts become legally binding.
Both pushed their way through a crowd of journalists without comment. The trial, lasting one and a half years, was widely seen as the last major attempt by united Germany to bring East Berlin's Communist leadership to book.
Honecker, who ruled for 18 years before being toppled and who would have celebrated his 85th birthday on yesterday, was released in the middle of his trial in 1993 because of ill-health. He died in 1994 in Chile.
Seven other senior East German figures, including the former defence minister Heinz Kessler, are serving three to six years after conviction last year on 15 counts of manslaughter and attempted manslaughter between 1980 and 1989.
Krenz had expressed regret during the trial for the deaths at the Wall around Berlin and at the border between the two Germanys, which victims' groups say exceeded 900. But he insisted that, as a satellite state of the Soviet Union, East Germany had no control over its borders. As a key part of his defence, Krenz presented a letter from the former Soviet president Mikhail Gorbachev, who criticised the court for holding Krenz responsible for the Cold War killings.
But Mr Hoch said prosecutors presented clear evidence that the East Berlin Politburo zealously turned broad guidelines from Moscow into the grisly machinery of death. "The Politburo was responsible for border security." Mr Hoch said. "The guards were in fact given an ideological order to shoot. The guards were taught that the refugees were enemies of peace and traitors to East Germany who should be destroyed."
Mr Hoch said that the East Berlin regime, fully aware that more than 2 million people had fled the country between 1949 and 1961, had built the Wall and made it increasingly lethal because they knew that it was the only way to keep the rest from leaving.
Krenz had planned to hold a news conference in a central Berlin hotel after the verdict. His son Carsten read a statement saying he planned to appeal to the European Court of Justice. "I will not beg the Federal Republic for mercy," Krenz said in the statement. "I was not convicted because of crimes, but rather because of my political position. The verdict is the Berlin state court's revenge for the existence of East Germany."