An army can be compared to a craftsmen. Both produce for gain. A craftsmen produces a product, a good, for monetary gain. An army, however, produces corpses for resource acquisition. Be it on the battlefield or in the medical tent with the severely wounded being put out of their misery, the fillers of graves are being produced.
Any mind of the modern age has thought about putting those bodies to work. Necromancy has long been socially inacceptable. Besides, no one enjoys seeing a former comrade, a former brother-in-arms, walking around fighting and killing with a spear hole in his gut and a couple arrows hanging from the arms. And the only other way was to throw the dead body into a catapult and throw it at the enemy, in the hopes of giving them plague.
It was Obstarian military who first unleashed the Raveten on their foes during the World War. No one was prepared for it. And so people died.