So did the HRE ever combine themselves against a common enemy

>>2935691
The HRE only became super decentralized after the death of Frederick II in 1250.

https://en.wikipedia.org/wiki/Holy_Roman_Empire#Interregnum

I'll do it since someone is bound to do it at some point
>H
>R
>E

They fought as a pretty cohesive entity in the Great Turkish War.

was there a Kingdom of Germany within HRE or is it just a bunch of regions named that?

>>2936044
"Germania" was purely a geographic term.

>>2936044
IIRC the kaiser was usually crowned King of the Germans as well

>>2936044
In the early times the HRE was made of four constituent kingdoms: Germany (which was composed of all the major duchies), Italy, Burgundy, and Bohemia. The actual title of emperor was generally conferred pretty late in the reign of the Emperpr, so he spent most of his time as the King of the Germans. The elective nature of the HRE came from the Germanic tradition of the king being merely the first amongst equals of all the leading groups. The heir apparent would also be named the King of the Romans, although that didn't come with any specific territory.