Katsumoto Saotome, a novelist who lived through the brutal American firebombing of Tokyo during World War II and worked relentlessly to preserve the memories of survivors in published accounts and at a museum he founded, died Tuesday in Saitama, a suburb of Tokyo. He was 90.

His daughter, Ai Saotome, confirmed the death. She said he had been hospitalized with pneumonia last fall.

Saotome spent more than half a century amassing the stories of survivors, some of whom were initially reluctant to share their recollections.