Please Help Identify Stamps C.1900-1940, Several Countries

Hi -- I have been working my way through an old shoebox of material that came my way. I only collect GB (and now starting US) and have no literature on any other countries. But the box also has material from several other countries, mostly in Europe.

I doubt they are worth anything, but would like to be sure. I have multiple copies of most of the stamps, so I am not worried about the condition of these individual examples. I just want to know if there is a gem in there -- and also if there were multiple look-alike issues where one version might be worth something while another is very common.

I start with Germany since that is the most prolific. Will add further scans as I can. Thank You.

Here are the other countries. Including: Austria, Belgium, France, Italy, Mexico, Netherlands, New Zealand, Philippines, Switzerland, Hungary (Empire?) and one from Soviet Union -- which I think is probably a stray from a different box in my office. There is also one I think may be a Tsarist Russia?

At the end are a couple of curiosities - four stamps that I think might be from pre-Revolutionary Russia and an Approval Sheet of numerous countries. I recognize: Belgium again, Poland, Czechoslovakia, Eire, Norway. There is a Republic of China - is that Taiwan? The top right could be pre-Revolution Russia again?

I would be grateful if someone can confirm if these 6 stamps are from Russia, and of what era? Also if anyone can identify the second row, third space (pale tan stamp), second row final stamp (light orange-brown), and the two purples on the next row: "Travancore Anchel"?

Thanks again for any information about any of this.

One last quick question -- there were three of these Fidelity Stamps approval sheets in the box. Two as seen here and one almost full of US stamps. I have not tampered with them -- is there any point /value / historical worth to keeping them intact?

JanS, I won't comment on the others because they're not my area, but I'd need to see good big individual scans of the two Travancore stamps before I could tell you if you have anything worthwhile. You'll probably have to check their watermarks and perforations as well.

Second row third is Austria (republic `Deutschösterreich` issued 1919/1920, imperforated).
The Hungarian is no Empire. Hungary was part of the Austro-Hungarian Empire till the end of I. WW- then for a short period became republic (1918-1919 march), then became The Hungarian Sowiet Republic, finally became Kingdom (from march 1920-although had no king, only a governor- in fact the governor (Horthy) itself was defeating the last Austrian Emperor and Hungarian King who attempted to regain the throne in Hungary). After II. WW Hungary became again republic. The stamp is issued in 1932, 20 filler red, depicts Ferenc (or Franz) Liszt, composer.
The two larger Belgium stamps are packet-stamps, issued in 1929/1930.

Couple of stamps in row one of scan 1 and the block of 6 are hyperinflation stamps from Germany (as indicated by the 'million' overprints).