I don't think they were made specifically for the German military, although they certainly may have used this style of watch.
Many different manufacturers made a watch like this, from small companies like Recta and Helvetia to well known names
like Breitling, Omega and Zenith.
They were generally designed for pilots of the period, a true tool watch.
I have heard the design called "Luftwaffe Pattern", but believe this is a misconceived nickname.
Here is a similar design listed in Breitling's 1946 Catalogue.

