Since the early 1960s Simon Wiesenthal’s name has become synonymous with Nazi hunting. His standing is that of a secular saint. Nominated four times for the Nobel peace prize, the recipient of a British honorary knighthood, the US Presidential Medal of Freedom, the French Légion d’honneur and at least 53 other distinctions, he was often credited with some 1,100 Nazi “scalps”. He is remembered, above all, for his efforts to track down Adolf Eichmann, one of the most notorious war criminals.

His reputation is built on sand, however. He was a liar — and a bad one at that. From the end of the second world war to the end of his life in 2005, he would lie repeatedly about his supposed hunt for Eichmann as well as his other Nazi-hunting exploits. He would also concoct outrageous stories about his war years and make false claims about his academic career. There are so many inconsistencies between his three main memoirs and between those memoirs and contemporaneous documents, that it is impossible to establish a reliable narrative from them. Wiesenthal’s scant regard for the truth makes it possible to doubt everything he ever wrote or said.

Some may feel I am too harsh on him and that I run a professional danger in seemingly allying myself with a vile host of neo-Nazis, revisionists, Holocaust deniers and anti-Semites. I belong firmly outside any of these squalid camps and it is my intention to wrestle criticism of Wiesenthal away from their clutches. His figure is a complex and important one. If there was a motive for his duplicity, it may well have been rooted in good intentions. For his untruths are not the only shocking discoveries I have made researching the escape of Nazi war criminals. I found a lack of political will for hunting them. Many could have been brought to justice had governments allocated even comparatively meagre resources to their pursuit.

It is partly thanks to Wiesenthal that the Holocaust has been remembered and properly recorded and this is perhaps his greatest legacy. He did bring some Nazis to justice; but it was in nothing like the quantity that is claimed and Eichmann was certainly not among them. There is no space here, however, for my forensic examination of his claims as a Nazi hunter. I will confine myself to some famous episodes before and during the war that are at the heart of the Wiesenthal myth.

He was born in 1908 in Buczacz, Galicia, then part of the Austro-Hungarian empire and now in Ukraine. After the first world war, Buczacz changed hands frequently between Poles, Ukrainians and Soviet forces. In 1920 the 11-year-old Wiesenthal was attacked with a sabre by a mounted Ukrainian who slashed his right thigh to the bone. Wiesenthal regarded the scar as part of a long line of evidence that he was protected from violent death by an “unseen power” that wanted him kept alive for a purpose.

His background was ideal for any aspiring fabulist. Like many from Galicia, Wiesenthal would have spent his childhood immersed in the Polish literary genre of tall stories told over the dinner table. In a place such as Buczacz in the 1920s, truth was a relatively elastic concept. At 19 he enrolled as an architectural student at the Czech Technical University in Prague, where he found his metier as a raconteur and appeared as a stand-up comedian.

His studies went less well. Although most biographies — including that on the Simon Wiesenthal Center’s website — say he graduated, he did not complete his degree. Some biographies say he gained a diploma as an architectural engineer at Lvov polytechnic in Poland, but the Lvov state archives have no record of his having studied there and his name is absent from Poland’s pre-war catalogue of architects and builders. He claimed fraudulently throughout his life that he did have a diploma; his letterheads proudly display it.

Similarly, there are large discrepancies in his dramatic stories of the second world war. He was in Lvov when it fell to the Nazis in 1941. He claimed he and a Jewish friend called Gross were arrested at 4pm on Sunday July 6, one of the few dates that remain constant in his ever-shifting life story. Whenever he is so specific, however, he is usually lying.

Frogmarched to prison, they were put in a line of some 40 other Jews in a courtyard. Ukrainian auxiliary police started shooting each man in the neck, working their way down the line towards Wiesenthal. He was saved by a peal of church bells signifying evening mass. Incredibly, the Ukrainians halted their execution to go to worship. The survivors were led to the cells, where Wiesenthal claims he fell asleep. He was woken by a Ukrainian friend in the auxiliary police who saved him and Gross by telling them to pretend they were Russian spies. They were brutally questioned — Wiesenthal lost two teeth — but were freed after cleaning the commandant’s office.

The story of this sensational escape — one of the most famous of Wiesenthal’s war and one that has helped to establish the notion of his divine mission — is in all likelihood a complete fabrication. Certainly the Ukrainians carried out brutal pogroms in Lvov in early July 1941; but there was then a pause and they did not start again until July 25. According to testimony Wiesenthal gave to American war crimes investigators after the war, he was actually arrested on July 13 and managed to escape “through a bribe”. By subsequently placing his arrest on July 6, his story fitted the timing of the pogroms.

By the end of the year Wiesenthal was in Janowska, a concentration camp outside Lvov. Given the task of painting Soviet railway engines with Nazi insignia, he made friends with Adolf Kohlrautz, the German senior inspector at the workshop, who was secretly anti-Nazi. On April 20, 1943, Wiesenthal was apparently selected for a mass execution again. The SS at Janowska picked him among some Jews to be shot in a grim celebration of Hitler’s 54th birthday. They silently walked towards a huge sandpit, 6ft deep and 1,500ft long. A few dead bodies were visible in it. Forced to undress, they were herded in single file down a barbed-wire corridor known as the hose to be shot one by one at the edge of the pit.

A whistle interrupted the gunshots, followed by a shout of “Wiesenthal!” An SS man called Koller ran forward and told Wiesenthal to follow him. “I staggered like a drunk,” Wiesenthal recalled. “Koller slapped my face twice and brought me back to earth. I was walking back through the hose, naked. Behind me, the sounds of shooting resumed but they were over long before I had reached the camp.” Back at the workshop he found a beaming Kohlrautz, who had convinced the camp commander it was essential to keep Wiesenthal alive to paint a poster that would feature a swastika and the words “We Thank Our Führer”.

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