Gunka no Balzer

Gunka no Balzer is a seinen manga by Nakajima Michitsune, where an officer from an military superpower is assigned to an ally's military academy to teach the student body of a Military Academy the modern ways of war.

The story is set in an alternate 19th century in Europe. Fifty years ago, The Empire collapsed into several successor states with successive periods of war and peace. One of those states, Weissen grew to be one of the dominant powers in the region. Weissen Army Major Bernd Balzer is a rising star due to his distinctions earned in battle. His career takes a surprising turn when he is suddenly reassigned as an adviser and military academy instructor to the newly-allied state of Baselland.

But, its army is out of shape for contemporary war and the citizenry are hostile to anything related to war or the military. As an instructor, Balzer has to deal with Baselland officer corps’ antiquated understanding of military theory and practice in order to be prepared to fight the next war, whenever it breaks out.

Tropes used in Gunka no Balzer include:

Armies Are Evil: Baselland’s civilians are staunchly anti-militaristic, and it shows in their attitudes toward Weissen and Balzer's gun salute.
Bling of War: The Prussian-esque uniforms of the Weissen Army and the uniforms of the Baselland cavalrymen.
Ensign Newbie: Helmut Marx von Babel.
Fantasy Counterpart Culture: Weissen is very much like Prussia, while Baselland resembles one of the other German states before the 1871 Unification.
Great Offscreen War: A civil war (with successive periods of pieace) caused by the collapse of The Empire 50 years ago is briefly mentioned. Though the siege against the Northern Trade Duchy in the beginning may be part of that war.
Hidden Elf Village: Baselland was spared the destruction of recent wars due to its geographical location and was able to thrive as a result. However, the isolation meant that Baselland was unable to develop a railroad network and military developments in theory and practice have stagnated to Napoleonic mass formations and smoothbore muzzle-loaders.
Hollywood Tactics: Ryner's "shooting trial" has a 50-man platoon armed with smoothbore muzzle-loading muskets--close order drill and all pitted against Balzer's handful of men equipped with bolt-action rifles. The results would not be dissimilar to any Prussian in 1866...
Magnetic Hero: Balzer to the Baselland Military Academy students. His genius, nice personality, good speaking skills and helping hand to defend them makes the students in the Cavalry, Artillery and Infantry look up to him. Another reason Balzer is nice to the students is because if he acted like a jerkass to them, they won't hesitate to shoot him in the back in the future.
Royals Who Actually Do Something: Ryner maybe a hardass but at least he cares about improving the Baselland military using his inheritance money compare to his older brother, the Crown Prince, who mostly spends his money on parties, girls and has no interests in politics.
Shown Their Work: When the artillery officer cadets prep their guns to fire for a salute, the process in loading, aiming and firing cannon is shown in meticulous detail.
The Mole: Weissen not only sent Balzer to Baselland to teach but also spy on their military strength as the Weissen government wants to annex Baselland into their country whether by peaceful or hostile means. Balzer is uncomfortable with this.
The Neidermeyer: Ryner August Winkfeldt, also a Royal Brat.