If you want the option to pack maximum tear-inducing misery in a story , the teenage years of someone born in Japan around 1933 is a pretty good setting. Poverty, starvation, ruins, gangs of orphan children, shell-shocked homeless soldiers, the awareness you were raised in a world of lies...
edit: I (...don't...) recommend looking up a manga named Cocoon. It's a historically informed story about a class of schoolgirls during the Battle of Okinawa IIRC, slightly yuri and really fucking depressing.
The movie Grave of the Fireflies is gritty and depressing look into the lives of Japanese war orphans. I get a little teary eyed just mentioning it.
Barefoot Gen manga. So good, so sad.
