Barefoot Gen (1973)

Set in the year of 1945 in Japan, Gen Nakaoka is an easy-going 6-year-old boy who lives with his poor yet loving family. As the second World War occurs, Gen's father Daikichi are one of the few who stands against the emperor and stand for the innocent citizens who are wounded from the war. Unfortunately, Gen and his family are seen nothing as traitors. Unbeknownst to them, a horrible fate awaits the people of Hiroshima.