Germany, What Do I Have, New And Old (Hitler Era)

I know some of these are from the 60s maybe early 70s as I had a pen-pal in Germany for a couple of years back then, but some are obviously much older.
I assume some date at least back into the 1940s because of the image of a certain historical figure, but I'm wondering about most of these.
When, what, especially some that seem to have been over-printed with new numbers (the black print) and then there's a really small one in the mix - about 1/4 the height of a typical stamp, what is it?
I'm trying to organize and these have been in a glassine envelope for years, many duplicates I've sorted out. I'd like to start putting them in an album, but would love to know era and some info first - if possible.
Thanks.
And yes, I'm a "rank amateur", probably in the bottom 5% here, I admit it.

The numerically overprinted stamps and high values that are not overprinted (1000 to 50 million Mark) stamps are from the inflation period of 1922-23, mostly 1923. They are prolific mint, but genuine used stamps can have more value. NOTE: Fake cancellations are abundant.

The small Berlin stamp is a postal tax stamp from the 1940's blockade era.

Thanks for the information. Most of these I obtained when I was a kid of about 10 or so, that means late 1960s. I bet I bought them in a bunch of German stamps at a store where you could get the 'grab bags' of stamps on a budget.
Probably of little real value, but it's nice to know more about history through stamps like this.

The little 'Berlin' stamp is colloquially referred to as the Blue Flea.

Here is a great exhibit with more than you wanted to know:

https://www.germanyphilatelicsociet...its-travels/

You can also search here on SCF for Notopfer or Blue Flea for some older threads.

Thanks! (to both). Interesting name........
I guess I seem to concentrate on the non-US countries that have some sort of connection to me or family. First wife was grand daughter of German immigrants, current wife also of German ancestry if you go back far enough.
Daughter-in-law is Korean, other son married a Chinese lady and lives in China.
And I've been to Israel, so have an interest in those.
(not to leave out Australia, Austria, Russia (I used to work in a company founded by Russians, and friends with a former Soviet military officer)

Thanks for the clues on the German items - now I can dig and read.
And I hadn't thought of an inflationary period after WWI - but it makes a lot of sense. What a person learns through stamps.........