'November 9: How World War One Led to the Holocaust' examines the speeches both public and private of Hitler to try to solve the riddle of how a dictator could morph into the industrial-scale murderer of an entire people.
"The core of his hatred lies at the defeat of Germany in WW1," said Mr Riecker, "where Hitler blamed the Jews for defeat of the country, the collapse of the monarchy and the ruination of millions".
Dr Riecker discounts previously held theories that Hitler began hating the Jews because a Jewish doctor called Eduard Bloch unsuccessfully treated his mother Klara.
He added: "Adolf Hitler loved only two things in his life: his mother and the 'German Reich'.
His mother died in 1907 very painfully from breast cancer which was seen at that time as the result of blood poisoning.
"Hitler saw the state 'poisoned' from within. Hitler lived in Munich, where Jews played a leading role in the revolution against the monarchy on Nov. 9th 1918. So suddenly the delusion came to his mind, that the Jews where the reason for the 'inner poisoning' of Germany and that they had stolen the victory from Germany," Mr Riecker said.
"And since this delusion revived the traumatic experience of the death of his mother, he developed the fanatic will to annihilate the "Jewish poison" – and thought that killing the Jews was the way to lead Germany to world domination.
"His anti-Semitism had nothing to do with Dr Bloch."
"Mr Riecker has produced an important and informative work," said German news magazine Der Spiegel in a