The allies had reports of the camps from almost the moment they existed, Im not sure how credibly they took those reports however. The camps in fact werent set up until early 1942. There is debate as to when the government decision to murder the jews was taken, as nobody can pin a date down anywhere within about a 6 month period in mid-1941... until that time the favoured policy was containment and then eventual emigration of the jews to Siberia. The two most popular theories are that Hitler made the decision when he thought he was about to win the war in Russia, in summer 1941, and he now felt he was invincible and could do anything he wanted without repercussion. This is the 'Intentionalist' argument - that Hitler had always intended to kill the Jews and when he saw an opportunity to do so, he took it. These historians see meetings in mid July between Hitler and his staff, including Himmler were held and orders were sent out to the SS fighting on the eastern front to no longer send Jews back to Polish ghettos, but to kill them. However, regardless of how much Hitler and Himmler went back, they were not exactly best buds like you may think - Himmler had to schedule an appointment with Hitler just like anybody else, and often Hitler was unavailable as he was in the Eagles Nest relaxing. Many of those in Hitler`s closest entourage had been with him from the beginning, and he trusted them only a little, and they held his good grace only as long as they pleased him - Himmler was no different from the others in this respect. The second theory - Structuralism, that it was the structure of the Reich that led to increasingly radical policies, is more popular today. Structuralists say the decision was taken later in the year, in autumn and winter, when it was obvious that the war on Russia was in trouble as the winter approached, and the murder of the jews was taken as a desperate measure now the emigration plan was obviously not about to happen. The local SS captain, Hoppner, as early as July 1941, had predicted the problem of overpopulation in the ghettos, and asked his superiors if there was a more human alternative to starving them to death, as it was becoming a health hazard. In October 1941 further German successes pushed even more Jews back from the Russian front and into the same ghettos that were already overcrowded, and the local SS officers had no option but to murder en masse to make room for the new entrants, and the first death camp was constructed locally to deal with the overflow in Lodz. There is a final argument, similar to the second, but which moves the date even further back, to a meeting in 12th December 1941... four days after the US joined the war. Historian Galach sees this as the final turning point, the final message to Hitler he had lost, and so he turns in rage on the Jewish population and sets out to kill them all. Either way, it took some months for the camps to be constructed and the clearing of the ghettos didnt get underway until lter on in 1942, and in November 1943 the death camps were closed down as the ghettos had been cleared. He moved to micromanage military affairs to an extreme degree only later in the war, when the repeated defeats in the Eastern Front meant he no longer trusted his generals and he took direct control. However it is true that he had always taken a great interest in the strategy of the german army. He had also taken enormously detailed interest in the architecture of the new empire he wanted to create, as the miltary and architecture were his two greatest hobbies. The day to day workings of the state both baffled and bored him, and he did his very best to remove himself from them. German historian Hans Mommsen saw Hitler as a weak leader, dependent on advisors, obsessed with prestige and unable to give direct orders, only general guidelines for future action. This is simply wrong. The German economy was overheating as Hitler ran it beyond it`s capacity to generate the great German economic revival of the 1930s, and rebuild the military from its Treaty Of Versailles restricted levels. But the system he created was unstable, it was expanding beyond Germany`s ability to support it and without extra fuel it would implode. There were no camps. The systematic murder of Jews began not in camps, and not with poison gas. The sytematic murder of jews began on a local level in Poland and conquered Russian territories, with mass shootings usually by local police units. The decision to turn the machinery of the state to mass murder was no doubt approved by Hitler, but it did not originate with him, and his personal ideology did not specifically demand the murder of the jews, although when presented with it as a possible solution he would certainly have accepted it. Your original argument here was that the war was genocidal, and so was Hitler`s ideology. This simply wasnt the case. The war was never intended to be a genocidal one, although it was intended to end with no jews in Germany. Similarly Hitler knew only that he wanted no Jews to remain, but never had any clue of how to achieve that and probably never foresaw the mass murder as a realistic objective. That is simply not true. Hitler was NEVER interested in personal aggrandisement, even at his death he was obsessed with GERMAN power, and GERMAN aggrandisement, although by then he had come to believe the two inextricably interlinked On a personal note... Ive kind of forgotten what the point of all this was. It seems to have turned into me giving a seminar on the Hitler and the holocaust.