The Wehrmacht helmet that might have been

[uk 75]

One of the most chilling sights for tourists in East Berlin before 1990 was the changing of the guard by East German Peoples Army (NVA) soldiers. Like their Soviet comrades they used the infamous goose step while their AK rifles were similar to the late war Sturmgewehr. But it was their uniform and helmets that completed the image.
In fact the helmet had been trialed by the Wehrmacht but never adopted.

Why did east German soldiers wear weird helmets?

Answer (1 of 6): From Wikipedia: M1956[edit] M1956 East German Stahlhelm The East German M-56 helmet was originally designed in 1942 as a replacement for the M1935/M1940 model Stahlhelm. It was initially developed for the Wehrmacht by Prof. Dr.-Ing. Fry and his collaborator Dr. Hansel from the...

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[Jemiba]

This helmet is said to have been very good, much better, than the previous Wehrmacht models M35 and M40.
So, it was a good choice for the NVA, but probably at least as important was the fact, that back then photos of
Wehrmacht soldiers wearing it, seemed to be non-existent. Otherwise it would have had to be another model,
I think. Such a connection between Wehrmacht and NVA certainly would have been inacceptable, no matter,
how good that helmet was. Striking, how those relatively small differences in the shape of helmets make for
unmistakeable appearance of soldiers ... except, maybe, for the German platoon in "The Longest Day", which
passes by a US one (but one without John Wayne !), without noticing that small difference. Very much to their
disadvantage ...

 

[riggerrob]

A similar helmet was issued to British and Canadian soldiers for the D-Day landings. The steel Helmet, Mark III was deeper, with shallower sloped sides to better protect soldiers' heads. It was deeper than the World War 1-vintage Brodie helmet and provided better protection for the sides of the head.
Brodie and Mark III helmets are difficult to distinguish in war-time photos because soldiers concealed both with net or cloth camoflauge.
The Mark IV steel helmet was minor improvement introduced after WW2 and it remained in service until replaced by fibreglass helmets during the 1980s.

 

[Pioneer]

I've just recently begun to appreciate the history and engineering of the M-56 helmet.

Regards
Pioneer