[1] Harada was born on 16 November 1928 in Dairen, Manchuria, which was then part of the Empire of Japan; his father was a Japanese army officer.

[7] Following completion of his tertiary studies, Harada took a position with the Bank of South America in São Paulo, Brazil.

In the period that followed, political troubles saw many of Funakoshi's senior students (including Harada) form the Shōtōkai group separate from the JKA.

[8] At the time, karate students in Paris had heard of him and saved enough money to buy him an airline ticket to their city; Harada resigned from the bank, intending to take a year to travel before returning to Brazil.

[1][2] Harada returned to Japan for six months in 1967 and, while he apparently did not consider the journey fruitful overall, he did confirm a replacement to lead his dojo in Brazil: Arinobu Ishibata.

[9][10] Harada has also taught at other overseas clubs that were developed including: Canada, Estonia, Finland, Gibraltar, Israel, Morocco, Poland, Spain, and the USA.

In October 1998, the Nihon Karate-do Shotokai invited Harada back to Tokyo to demonstrate his art as part of Shotokan karate's 60th anniversary celebration, and he and a selection of his top students did so.

[10] In 2007, Queen Elizabeth II appointed Harada as a Member of the Order of the British Empire for his services to karate.