Born in Kumamoto Prefecture, Japan, to a businessman father and mother who played the piano domestically, Yoko Nagae was exposed to music at an early age. Her parents separated when she was 8, and her father discarded the piano from the family residence. To continue playing the piano, she searched out neighbours' residences which had pianos. Nagae later studied harp at the Tokyo National University of Fine Arts and Music. She was briefly married to a university classmate, but this marriage ended in divorce. Following her graduation, she went to Florence, Italy in 1960 to continue her studies in harp. She placed 6th at the 1965 International Harp Contest. In 1962, at a Venice café, Nagae met Count Renzo Ceschina, a millionaire businessman from Milan approximately 25 years older than her. They began a long courtship, which culminated in their 1977 marriage, when Count Ceschina was about age 70. Count Ceschina changed his will after their marriage, bequeathing his entire fortune to his wife. Their marriage lasted until his death in 1982. Countess Ceschina ceased playing the harp after her husband's death. A nephew of Count Ceschina challenged the will in court, alleging that Countess Ceschina had forged her husband's signature. After 10 years, the case was settled in favour of Countess Ceschina, with confirmation that the Count's signature was genuine. Countess Ceschina claimed her inheritance, which was valued at the time at approximately $190M. Countess Ceschina subsequently sponsored such ensembles and musicians as the New York Philharmonic, Valery Gergiev and the Mariinski Theatre, Carnegie Hall, the Israel Philharmonic Orchestra, the International Harp Contest, and the National Youth Orchestra of the United States of America. On an individual level, she particularly supported Maxim Vengerov, such as in her contribution of half of the cost of Vengerov's 1727 Stradivarius violin. Countess Ceschina was a major sponsor of the visit by the New York Philharmonic to North Korea in 2008. In general, she rarely gave interviews, but regarding the controversies surrounding this concert, she publicly stated to various media organisations:
"I hope that this will lead to some good will. Even if I'm criticized, I believe in my position." "Music has no borderlines. It is good if people gain some happiness by listening to good music." "Non capisco assolutamente nulla di politica, ma so che la musica riavvicina le persone e parla un linguaggio universale. Spero di contribuire alla pace."
In 2011, Countess Ceschina endowed the music directorship of the New York Philharmonic, the first titled music director chair in the orchestra's history. In November 2014, she received the Russian "Order of Friendship" honour. Countess Ceschina died on 10 January 2015 in Rome, Italy at the age of 82. She was not survived by any children.
