If you've played HOI4 for more than a few months, the Kaiserin for Germany and the HRE are probably known to you. But since BBA forming the HRE has become a lot more difficult, or at least time consuming. I believe I have optimized the process and you should be able to form it in 1938 or early 1939 with this strategy. Enjoy!
Template note: it seems my template didn't show because I accidentally edited it out. I used the basic infantry template the Germans start with, but I added one artillery battalion after flipping to non-aligned.
All DLC's up until BBA were used in this video. Historical focuses are on, as is Ironman.
Music is from Age of Wonders 1
