Akihito was the fifth child and eldest son of Emperor Hirohito and Empress Nagako. During his early years he was reared in the traditional imperial manner, beginning his education at the Peers' School in 1940. He lived outside of Tokyo during the last years of World War II but returned to the Peers' School (from 1949 Gakushūin) after the war. Because of the changes the war had brought to Japanese society, not the least of which was the removal of the emperor's power to rule in any way other than ceremonially, Akihito's education was broadened to include training in the English language and in Western culture. His tutor was Elizabeth Gray Vining, an American Quaker. Like his father, he eventually took up marine biology as a field of endeavour. In 1952 Akihito came of age and was invested as heir to the Japanese throne. Seven years later, breaking a 1,500-year-old tradition, he married a commoner, Shōda Michiko, who was the daughter of a wealthy businessman. Michiko was a graduate of a Roman Catholic university for women in Tokyo. Their first child, Crown Prince Naruhito, was born on February 23, 1960; he was followed by Prince Akishino (b. November 30, 1965) and Princess Nori (b. April 18, 1969).

Akihito became emperor on January 7, 1989, after the death of his father. He was formally enthroned on November 12, 1990. His reign was designated Heisei, or “Achieving Peace.”