Kiyoshi Nagai (永井潔, Nagai Kiyoshi), better known as Go Nagai, was born on September 6, 1945, in the Ishikawa Prefecture city of Wajima. As is the case with many artists, Nagai used his drawing ability in school to gain acceptance among his classmates.
Multiple sources state that when Nagai was “young”, his father, Yoshio Nagai, passed away. However, the year and cause of Yoshio’s death is nowhere to be found. After doing some research of my own, I found a letter from Second Lieutenant, Yoshio Nagai, who, on June 8, 1945, died in a kamikaze mission at Okinawa.
The dots aren’t fully connected, but there might be something here. Nagai would have been in utero on June 8. That counts as “young”. And, it stands to reason that a kid whose father “fell honorably for the Emperor” while flying a mech, would get into drawing mechs piloted by heroes.
As a kid, Nagai found inspiration in Gustave Doré’s art for The Divine Comedy and in Osamu Tezuka’s Lost World. Tezuka’s work (including Astroboy) led Nagai to becoming a mangaka (manga creator).