Funny you should mention that, but on my 3 or 4 greats grandfather Etienne, the 1st to come to the US on his country of origin it say Empire of the Germans.
Well, until 1803, it was “Reich” In English, The Empire. In 1871, after the Franco-Prussian War, the king of Prussia assumed the title Kaiser and it is the Empire of the Germans. So we have a second Reich. There was another Reich, of course, that of the Austrians. Hitler aimed at unification of the German lands. a restoration of the First Reich, a Third Reich. One reason why the Western Powers were so willing to let Hitler have the Sudetenland was that it, like Austria, was German.