Mitoyo Kawate was born in Umaki, Hiroshima Prefecture, Japan on 15 May 1889. She had four children (a son and a daughter surviving as of 2003). She liked singing and had a weakness for custard cakes.
At the time of the Atomic bombing of Hiroshima on 6 August 1945, Kawate was on her farm, which was located about six miles away from downtown. In 1945, two days after the bombing, she entered Hiroshima City to look for acquaintances. Being exposed to radiation, she was considered a survivor of the bombing.
Kawate worked on a farm until she injured her hands at the age of 99. She moved to a nursing home in Higashi-ku, Hiroshima City in October 1993. Around 2001, she began to become weak.
Following the death of claimed 116-year-old Kamato Hongo on 31 October 2003 (support for her case was later withdrawn), Kawate was reported by Guinness World Records as the world’s oldest living person. Some days before her death, she was hospitalized for pneumonia.
Mitoyo Kawate died of pneumonia in Hiroshima City, Hiroshima Prefecture, Japan on 13 November 2003, at the age of 114 years, 182 days.
Following the death of 114-year-old Asa Takii on 31 July 1998, Kawate became the oldest living person in Hiroshima Prefecture.
Following the death of 112-year-old Matsuno Oikawa on 3 January 2002, Kawate became the oldest living woman in Japan. Following the death of 114-year-old Yukichi Chuganji on 28 September 2003, she became the oldest living person in Japan. However, she was reported as such following the death of Kamato Hongo (who claimed to be older than both Oikawa and Chuganji) on 31 October 2003, but support for her case was later withdrawn.
On 18 August 2003, Kawate surpassed Asa Takii‘s age, thus becoming the oldest person who ever lived in Hiroshima Prefecture. At the time of her death, Kawate was the fifth-oldest person who ever lived in Japan, after Tane Ikai, Hide Ohira, Tase Matsunaga, and Yukichi Chuganji.
Kawate became the world’s oldest living woman on 29 December 2002 with the death of 113-year-old Mae Harrington.