The following is a photo chronology of major events related to new Emperor Naruhito and his family.

Feb. 23, 1960 -- Prince Hiro, later Crown Prince Naruhito, born as first son of Emperor Akihito.

Dec. 9, 1963 -- Masako Owada born as eldest daughter of diplomat Hisashi Owada

[Supplied photo]

April 1978 -- Prince Naruhito advances to Gakushuin University.

September 1981 -- Masako Owada enters Harvard University

April 1982 -- Prince Naruhito advances to a graduate school of Gakushuin University

October 1983 -- Prince Naruhito enters University of Oxford's Merton College.

June 1985 -- Masako Owada graduates from Harvard University

[Supplied photo]

April 1986 -- Masako Owada enters University of Tokyo

Oct. 18 -- Prince Naruhito, Masako Owada meet for first time at welcoming reception for Spanish Princess Elena.

April 1987 -- Masako Owada joins Foreign Ministry

July 1988 -- Masako Owada moves to Britain to study at University of Oxford's Balliol College.

Jan. 7, 1989 -- Prince Naruhito becomes crown prince upon death of Emperor Hirohito, posthumously known as Emperor Showa.

August 1992 -- Crown Prince Naruhito, Masako Owada meet again at home of former diplomat Kensuke Yanagiya.

Oct. 3, 1992 -- Crown Prince Naruhito proposes to Masako Owada.

June 9, 1993 -- The two marry.

November 1994 -- The couple visits Middle Eastern countries on their first official overseas visit.

December 1999 -- Crown Princess Masako suffers miscarriage.

Dec. 1, 2001 -- Princess Aiko, the couple's only child, born.

[Photo courtesy of the Imperial Household Agency]

Dec. 12, 2003 -- Imperial Household Agency announces Crown Princess Masako will refrain from official duties due to stress-induced illness.

May 10, 2004 -- Crown Prince Naruhito tells press conference there were "developments that were regarded as denying Masako's career as well as her personality."

July 30 -- The agency announces Crown Princess Masako is suffering from adjustment disorder.

August 2006 -- The family stays in the Netherlands for a two-week sojourn aimed at helping Crown Princess Masako recover from her illness.

April, 2008 -- Princess Aiko enters Gakushuin Primary School.

March 5, 2010 -- The agency announces Princess Aiko has been unable to attend classes due to anxiety.

March 11, 2011 -- Earthquake, tsunami hit wide areas of northeastern Japan, triggering nuclear accident in Fukushima. The couple visits affected people at evacuation centers in following months.

April 28-May 3, 2013 -- The couple visits the Netherlands in what becomes Crown Princess Masako's first trip overseas in 11 years.

April 2014 -- Princess Aiko advances to Gakushuin Girls' Junior High School.

Aug. 8, 2016 -- Emperor Akihito releases rare video message expressing desire to abdicate and pass the throne to Crown Prince Naruhito.

April 2017 -- Princess Aiko advances to Gakushuin Girls' Senior High School.

June 9 -- Japan enacts one-off legislation enabling Emperor Akihito to abdicate.

June 9, 2018 -- Crown Prince Naruhito, Crown Princess Masako celebrate 25 years of marriage.

[Photo courtesy of the Imperial Household Agency]

July 22 -- Princess Aiko leaves for summer school program at Eton College.

April 1, 2019 -- Government announces new era name to be used during new emperor's reign as Reiwa.

April 30 -- Emperor Akihito abdicates as first Japanese monarch to do so in about 200 years.

May 1 -- Emperor Naruhito ascends the throne.