Masahito, Prince Hitachi

Masahito, Prince Hitachi (常陸宮正仁親王) is a member of the Imperial House of Japan, the younger brother of Emperor emeritus Akihito and the paternal uncle of Emperor Naruhito. He is the second son and sixth born child of Emperor Shōwa and Empress Kōjun and is third and last in line to the Chrysanthemum Throne. He is mainly known for philanthropic activities and his research on the causes of cancer.

Early life and education
Born at Tokyo Imperial Palace in Tokyo, Masahito held the childhood appellation Prince Yoshi (義宮正仁親王).

Masahito received his primary and secondary schooling at the Gakushūin Peers' School. In late 1944, the Imperial Household Ministry evacuated Prince Yoshi and the Crown Prince to Nikkō, to escape the American bombing of Tokyo.

After the war, from 1947 to 1950, Mrs. Elizabeth Gray Vining tutored both princes and their sisters, the Princesses Kazuko, Atsuko, and Takako, in the English language. Her account of the experience is entitled Windows for the Crown Prince (1952).

Prince Yoshi received his undergraduate degree in chemistry from the Faculty of Science at Gakushuin University in 1958. He subsequently did postgraduate work in the Faculty of Science at Tokyo University. In 1969, he became a Research Associate of the Japanese Foundation for Cancer Research specializing in the study of cellular division. The results of his research have been reported in the technical journals of the Japanese Cancer Association, as well as of the American Association for Cancer Research.

In 1997, Prince Hitachi received an honorary doctorate from George Washington University in the United States, and in April 2001 received another from the University of Minnesota. In March 1999, he became an honorary member of the German Association for Cancer Research, in recognition of his significant scientific contributions to the field of cancer research.

Marriage
On 30 September 1964, the Prince married Hanako Tsugaru (born 19 July 1940), fourth daughter of the late Yoshitaka Tsugaru, a former count and a descendant of the daimyō of Tsugaru Domain. The following day, Emperor Shōwa granted him the title Hitachi-no-miya (Prince Hitachi), and authorization to start a new branch of the Imperial Family in celebration of his wedding.

Prince and Princess Hitachi have their official residence in a palace in large gardens off Komazawadori in Higashi, Shibuya. They have no children.

In September 2021, the Japanese government considered plans to amend the Imperial Household Law and allow Prince Hitachi to adopt a male member of the former shinnōke or ōke collateral branches of the imperial family in an effort to address the Japanese imperial succession debate.

Public service
Prince Hitachi is the honorary president of a wide variety of charitable organizations, especially those involving international exchange. Most recently, Prince and Princess Hitachi visited Nicaragua and El Salvador, to mark the 70th anniversary of the establishment of diplomatic relations with both countries in October 2005. They also made a visit to France in September 2007 and Peru, marking the celebration of 110 years since the establishment of a Japanese community in this country, June 2009.

Health
Prince Hitachi suffered from fever in late February 2023 and was hospitalized on 1 March. He was diagnosed with ureteral stones for which he underwent ureteral stenting the day after at the Japanese Red Cross Medical Center. He was discharged from hospital on 5 March. On 21 March, he underwent ureteral lithotripsy and was discharged on 24 March. He was readmitted to hospital with a fever and loss of appetite on 2 April, and was subsequently diagnosed with a urinary tract infection. He was discharged from hospital on 24 April.

Titles and styles



 * 28 November 1935 – 1 October 1964: His Imperial Highness Prince Yoshi
 * 1 October 1964 – present: His Imperial Highness Prince Hitachi

National honours

 * 🇯🇵 Japan: Grand Cordon of the Order of the Chrysanthemum (28 November 1955)

Foreign honours

 * 🇩🇰 Denmark: Knight of the Order of the Elephant (28 September 1965)
 * 🇮🇹 Italy: Knight Grand Cross of the Order of Merit of the Italian Republic (22 November 1965)
 * 🇳🇵 Nepal: Member of the Order of the Benevolent Ruler (19 April 1960)

Honorary degree

 * George Washington University
 * University of Minnesota
 * Chiang Mai University

Honorary positions

 * President of the Japanese Society for the Preservation of Birds
 * President of the Japanese Society for Disabled Children
 * President of the Japan Institute of Invention and Innovation
 * President of the Japan-Denmark Society
 * President of the Dainippon Silk Foundation
 * President of the Japanese Society for Rehabilitation of Persons with Disabilities
 * President of the Japan Art Association
 * President of the Tokyo Zoological Park Society
 * President of Maison Franco-Japonaise
 * President of the Princess Takamatsu Cancer Research Fund
 * Honorary President of the Japan-Sweden Society
 * Honorary President of the Japan-Belgium Society
 * Honorary President of the Japanese Foundation for Cancer Research
 * Honorary President of Association Pasteur Japon
 * Honorary Vice-President of the Japanese Red Cross Society

Patrilineal descent

 * Imperial House of Japan


 * 1) Descent prior to Keitai is unclear to modern historians, but traditionally traced back patrilineally to Emperor Jimmu
 * 2) Emperor Keitai, ca. 450–534
 * 3) Emperor Kinmei, 509–571
 * 4) Emperor Bidatsu, 538–585
 * 5) Prince Oshisaka, ca. 556–???
 * 6) Emperor Jomei, 593–641
 * 7) Emperor Tenji, 626–671
 * 8) Prince Shiki, ???–716
 * 9) Emperor Kōnin, 709–786
 * 10) Emperor Kanmu, 737–806
 * 11) Emperor Saga, 786–842
 * 12) Emperor Ninmyō, 810–850
 * 13) Emperor Kōkō, 830–867
 * 14) Emperor Uda, 867–931
 * 15) Emperor Daigo, 885–930
 * 16) Emperor Murakami, 926–967
 * 17) Emperor En'yū, 959–991
 * 18) Emperor Ichijō, 980–1011
 * 19) Emperor Go-Suzaku, 1009–1045
 * 20) Emperor Go-Sanjō, 1034–1073
 * 21) Emperor Shirakawa, 1053–1129
 * 22) Emperor Horikawa, 1079–1107
 * 23) Emperor Toba, 1103–1156
 * 24) Emperor Go-Shirakawa, 1127–1192
 * 25) Emperor Takakura, 1161–1181
 * 26) Emperor Go-Toba, 1180–1239
 * 27) Emperor Tsuchimikado, 1196–1231
 * 28) Emperor Go-Saga, 1220–1272
 * 29) Emperor Go-Fukakusa, 1243–1304
 * 30) Emperor Fushimi, 1265–1317
 * 31) Emperor Go-Fushimi, 1288–1336
 * 32) Emperor Kōgon, 1313–1364
 * 33) Emperor Sukō, 1334–1398
 * 34) Prince Yoshihito Fushimi, 1351–1416
 * 35) Prince Sadafusa Fushimi, 1372–1456
 * 36) Emperor Go-Hanazono, 1419–1471
 * 37) Emperor Go-Tsuchimikado, 1442–1500
 * 38) Emperor Go-Kashiwabara, 1464–1526
 * 39) Emperor Go-Nara, 1495–1557
 * 40) Emperor Ōgimachi, 1517–1593
 * 41) Prince Masahito, 1552–1586
 * 42) Emperor Go-Yōzei, 1572–1617
 * 43) Emperor Go-Mizunoo, 1596–1680
 * 44) Emperor Reigen, 1654–1732
 * 45) Emperor Higashiyama, 1675–1710
 * 46) Prince Naohito Kanin, 1704–1753
 * 47) Prince Sukehito Kanin, 1733–1794
 * 48) Emperor Kōkaku, 1771–1840
 * 49) Emperor Ninkō, 1800–1846
 * 50) Emperor Kōmei, 1831–1867
 * 51) Emperor Meiji, 1852–1912
 * 52) Emperor Taishō, 1879–1926
 * 53) Emperor Shōwa, 1901–1989
 * 54) Masahito, Prince Hitachi