Documentary together with William Shirer’s “The Rise and Fall of the 3rd Reich” (whole chapters on hitler’s life as a boy, his Schickelgruber name, jewish heritage,his homelife his abusive father, his WWI military service as a courier and winning the Iron Cross from his jewish commanding officer). All of the book is well documented footnoted and cross referenced with actual correspondence between hitler and various thugs who worked with him, and the reactions of the Prussian officer class who were very sorry they ever supported him. His sex life is in their as well.
Another resource is the US intel full profile of hitler from WWII—compiled by the OSS, and a top psychiatrist. Predicted his suicide, claiming abandoned by the German People. Which is what he did- he said the surviving Germans were worthless- the ones dying for him... his legacy. A true lunatic and major incompetent misdirecting Germany’s resources to the detriment and loss of a war they could have won— had it not been for the Holocaust and slave labor for Krupp, Thyssen and IG Farben to name 3 major corporations.
Haven’t read Shirer, but I remember wading through Konrad Heiden’s Der Fuhrer in translation, written in 1944, pretty dense prose. A wealth of contemporaneous information in that, about his love affair with his niece, the internecine struggles for power between Adolf and other factions in the Party, how he ultimately emerged on top after the Putsch and its aftermath, what his close associates thought of him personally, his relationship with the homos before 1934, etc., etc., up to and including the big purge in 1934.