One of Japan's remarkable manga artists and writers, Keiji Nakasawa was standing behind the wall in his school's garden when the Atomic Bomb was dropped onto Hiroshima on 6 August 1945. It was the wall that saved his life that day. He was only six years old. He lost all members of his family except for his mother and an infant sister, who also died a few weeks after the bombing.
Nakasawa's commonly known manga series "Barefoot Gen" deals with the life in Hiroshima before the bombing ,the aftermath and the suffering that follows.
In 1961, after moving to Tokyo with his mother, he began his first drawings. When he lost his mother in 1966, due to the terrible effects of the atomic bomb, he decided to create a manga series related to his memories of the bombing.
In the Foreword of the first episode of Barefoot Gen, Nakasawa writes, "When I went to the crematorium to gather the ashes of my mother, I was shocked to see there were no bone particles left from her body. The radioactive residue of the bomb had destroyed even the smallest bit of bone in her body. The bomb had taken away everything from me, including my mother's bones. I was so full of anger that I swore I would never forgive the Japanese who started the war and the Americans who dropped the bomb."
In Barefoot Gen, the reader sees the life in Hiroshima before and after the bombing through the eyes of Nakasawa's alter ego, Gen. Nakasawa's depiction of the destroying effects of war upon people is amazing. He questions the sides (Japan & the USA) who caused the sufferings of the war they are in as well as the hypocrisy of the people in his hometown.
What is told by Nakasawa in Barefoot Gen causes the reader to wander away from the dreamy atmosphere of a comic strip and forces them to remind themselves that the story is real, which results in "a pain in the stomach" feeling.
An interview with Nakasawa
http://www.tcj.com/256/i_nakazawa.html

