I have to apologize on not being able to offer up any references at this time, folks.
I went through several books I have on Hitler and found nothing in the indices on this topic. I have an old copy of Mein Kampf, but it's a 1939 version with no index, and I didn't go thumbing though it; besides I doubt anything on Cromwell is in it, perchance someone with a mastery of this book (and there are several on this site) can comment on this. I got this notion from SOMEWHERE, y'all, but I can't recall where.
Sorry. I still stand by this position, though, but right now I can't prove it. Here are some similarities & dissimilarities below:
Similarities:
Both came to power after the collapse of ancien regimes.
Both were talented military men (Cromwell more so than Hitler perhaps, as Jamopy says, Cromwell was a genius on the battlefield).
Again, as Jamopy states, they both, if necessary would go into 'total warfare' mode.
Both had widespread popular support among their ethnicities.
Both were ruthless with opponents.
Both, of course, were dictators (as again, Jamopy says, the 'fuehrerprinzip') with the illusions of having legislative bodies granting them power.
Both were DIEHARDS, i.e., the kinda' guys you have to KILL in battle because the don't surrender.
Both were Germanic men.
Both had blond skin (light); both had blond irises (blue).
Both were political geniuses.
Neither wanted to be king/emperor in their respective countries.
The both deported people they didn't like.
Both ruled a little over a decade.
Both built up the militaries of both countries.
Both were popular in the military circles of both countries.
Both waged war against Scotland & Wales.
Both were GOOD at foiling plots against their rule.
Both waged war against Holland.
Both were born in years ending in the # -9.
Both were born in April (Crom. the 25th; Hit. the 20th)<--this is probably one reason right here that Hitler identified with/liked Cromwell so much.
Dissimilarities:
Cromwell's rule endured, Hitler's didn't.
Hitler was a 'commoner,' Cromwell was a nobleman.
Cromwell was English, Hitler was Austrian.
Hitler was single with no children, Cromwell was a family man w/kids.
Cromwell was a fanatical religious crusader (the 'Joshua' of his day), Hitler was an a-religious opponent of religious war.
Hitler was opposed to both 'judaism' and the so-called 'jewish ethnicity;' Cromwell was at the very least indifferent to either element (one reason for this was perchance out of vengence against his anti-'jew' Anglican & Catholic opponents.
Cromwell was 'Protestant' (Puritan); Hitler was Catholic (if in name only).
Hitler entered politics at around age 30 Cromwell did about around age 40.
Cromwell was evidently auburn-haired (I know his picture below looks brown, but Stephen Douglas of The Redhead Encyclopedia has him listed as red...so, auburn is probably the truth); Hitler was brown-haired.
Hitler made no war against Ireland Cromwell did (bordering on a genocidal one).
Cromwell waged war against Spain Hitler did not & was even friendly toward Spain.
Hitler commited suicide, Cromwell died a natural death.
Cromwell waged war against Portugal, Hitler did not.
That's all I can think of at the moment, folks! lol

Also, one more thing about Cromwell...it was true that he let the 'jews' back in/tolerated them (whereas the Catholics & Anglicans among all the ethnicities in the Isles did not), but he was also not only a
violent opponent of Catholicism but also of Anglicanism...
So, strictly speaking, his opponents consisted of more than just Catholics. He ended up being no big fan of Scottish Presbyterianism either, but for them he did have some degree of tolerance. He always longed for a 'Protestant alliance' (England, Scotland, Prot. Ireland, Holland, N. German states, Denmark, Norway, Sweden, Huegenots, et al.) against Catholicism...that never happened, of course, much to his regret.
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