I know how you feel. I grew up reading years worth of Warlord, Victor and Commando comic strips. I watched a hundred and one films and documentaries about Hitler and WW2 on the TV and at school.
I never really understood what happened.
The history - Hitler , Austrian by birth, lucky lunatic, former male prostitute and failed artist, just happened by pure chance to attain control of the levers of power in Germany, and proceeded to just bring madness and mayhem to the peoples of Europe for a few years before he killed himself in his underground bunker.
He just irrationally "had a hatred" of the Liberals, Jews, Homosexuals, Communists, Slavs, Bankers, Gypsies and such, and thought that he should build a master race by killing all of the including the old, crippled and mentally handicapped.
Remember the next time Benedict XVI lectures about abortion - the Vatican and Pope Pius XII said NOTHING about the mass killing of the mentally handicapped and crippled - NOTHING.
There are in the above facets of truth amongst the lies, mistruths and wartime Allied propaganda blind alleys. All useful idiots need to be vulnerable to blackmail, and Hitler had more than a few skeletons in his closet - just like Barack H. Obama does today. It's why Hitler followed the Vatican script right to the end.
The truth is that the Roman Catholic Church was directly behind and supportive of Adolf Hitler personally and the Nazi German regime generally. They were up to their elbows in the killing.
For example: Pope Pius XII knew that the Croatians were mass murdering the Orthodox Serbs, if they wouldn't grovel to the Croatian Romanist Priests and convert. He certainly knew this:
The role of the Vatican in Yugoslavia's Holocaust (Link here)
When he met Pavelic on April 16th 1941, he later noted that he had promised that he would "not show tolerance" to the Orthodox Serbian church - which gave Stepinac the impression that Pavelic "was a sincere Catholic". By June 1941, when German army units were reporting that the "Ustashe have gone raging mad" killing Serbs, Jews and Roma, Catholic priests, notably Franciscans took a leading part in the massacres, as pointed out by Cornwell:
"Priests, invariably Franciscans, took a leading part in the massacres. Many, went around routinely armed and performed their murderous acts with zeal. A Father Bozidar Bralow, known for the machine gun that was his constant companion, was accused of performing a dance around the bodies of 180 massacred Serbs at Alipasin-Most. Individual Franciscans killed, set fire to homes, sacked villages, and laid waste the Bosnian countryside at the head of Ustashe bands. In September of 1941, an Italian reporter wrote of a Franciscan he had witnessed south of Banja Luka urging on a band of Ustashe with his crucifix." (p 254).It is clear now, that other members of the Catholic Cardinals in Europe also knew about the massacres. On March 6th 1942, a French Cardinal Eugène Tisserant, a close confident of the Pope to the Croatian representative to the Vatican:
"I know for a fact, that it is the Franciscans themselves, as for example Father Simic of Knin, who have taken part in attacks against the Orthodox populations so as to destroy, the Orthodox Church. In the same way, you destroyed the Orthodox Church in Banja Luka. I know for sure that the Franciscans in Bosnia and Herzegovina have acted abominably, and this pains me. Such acts should not be committed by educated, cultured, civilized people, let alone by priests". (p 259)The Catholic Church took full advantage of Yugoslavia's defeat in 1941 to increase the power and outreach of Catholicism in the Balkans - Stepinac had shown contempt for religious freedom in way that even Cornwell says was "tantamount to complicity with the violence" against Yugoslavia's Jews, Serbs and Roma. For his part, the Pope "was never but benevolent" to the leaders and representatives of fascist Croatia - in July 1941 he greeted a hundred members of the Croatian police force headed by the Zagreb chief of police; in February 1942, he gave gave an audience for Ustashe youth group visiting Rome, and he also greeted another representation of Ustashe youth in December of that year. The Pope showed his true colours when in 1943 he told a Croatian papal representative that he was:
"Disappointed that, in spite of everything, no one wants to acknowledge the one, real and principal enemy of Europe; no true, communal military crusade against Bolshevism has been initiated" (p 260)Stepinac for one, appears to have been a full supporter of forced conversions - along with many of his bishops, one of whom described the advent of fascist Croatia as "a good occasion for us to help Croatia save the countless souls" - i.e., Yugoslavia's non-Catholic majority. Throughout the war, Croatian bishops not only endorsed forced conversions, they never, at any point, dissociated themselves from Pavelic's regime, let alone denounce it or threaten to excommunicate him or any other senior member of the regime.
