There was a brief craze on the army for getting blood type tattoos. I never bothered, because with my luck I'd lose the part of my body with the tattoo on it.
Wan;t this standard in the SS during WW2??
I read that in some cases a German prisoner surrendered but was shot when they saw a blood group tattoo - as this was standard for all SS soldiers
Problem was that often if a normal soldier was injured and taken to an SS hospital then they would automatically tattoo him anyway
so a few normal soldiers were shot just because they had been treated in the wrong hospital
Not accusing anyone of anything - clearly everyone is far too young and any Army they might have been in wore different uniforms anyway
just an interesting historical point