The Duke of Sussex moved to Canada temporarily with his wife, the Duchess of Sussex, in 2019
The Duke of Sussex has said he "slipped into depression for about two weeks" after relocating to Canada in 2019 ahead of his move to the US.
Prince Harry, who recently returned to the UK with his wife Meghan and their two children, said he had originally left the country to "get some space."
The duke also discussed feeling "emotionally numb" after the death of his mother Diana, Princess of Wales, because he felt "disloyal and guilty for the possibility of being happy and joyful without her".
He opened up about his mental health with a neuroscientist in a session for a video learning platform.
He and his brother, the Prince of Wales, have previously been candid about their mental health struggles, including over their mother's death, and both are involved in mental health charities.
Prince Harry, who stepped back from royal duties to move to California with Meghan, made the latest comments as part of a paid-for online masterclass on dealing with grief.
"Being in Canada, away from the stressful environment where presumably my body was just pumped full of adrenaline, within two or three days, I experienced this adrenaline crash, something that I'd never experienced before," he recalled.
"It was as if I needed stress in order to get the adrenaline to make my brain function because I became useless around the house.
"I actually slipped into depression for about two weeks and I felt like I couldn't function without adrenaline."
Prince Harry says it is 'great' to be back in Britain after six years in US
Will Harry's return heal deep-rooted rift with William?
He and his wife unexpectedly announced last month that they were returning to the UK with their children Prince Archie, seven, and Princess Lilibet, five, after spending six years in the US. They are now thought to be living in the Cotswolds.
In the video, Prince Harry also revealed that he had a rule that he would never be away from his family for more than 10 days.
He talked about struggling to process his grief in the years after the death of his mother when he was 12.
"In my 20s, I went to war twice thinking I could outrun my feelings," the duke said, referring to his stints in Afghanistan as a member of the Army. "But that's not what happened.
"I'd spent so long emotionally numb, to a large extent, because I felt disloyal and guilty for the possibility of being happy and joyful without her.
"I felt like I had to be sad and I had to be emotionally numb in order to prove to her that I missed her."
Prince Harry said he struggled to process his grief for years after the death of his mother Diana, Princess of Wales
Prince Harry said in the discussion that after crying at Diana's funeral, he did not cry for nearly two decades, according to news outlets.
He said it was a therapist who suggested he spray her perfume to "unlock everything", adding that this allowed him to discover that "she just wanted me to be happy".
Mary-Frances O'Connor, a neuroscientist and University of Arizona professor who also featured in the online class, explained: "Your brain doesn't register your loved one as gone – it registers them as lost.
"And it will keep searching until you teach it otherwise. We still expect that they're going to walk through the door."
MasterClass approached Harry about appearing in the programme last year and it was filmed in California over the summer, according to People magazine.
Details of help and support with mental health are available at BBC Action Line.
Harry interview 'following Diana's example'
William reveals mental health pressures
William: Parenthood 'resurfaced Diana memories'
Catherine joins William as he says sport can save lives from suicide
Watch our pick of standout clips from across the BBC
Labour wins Holborn and St Pancras by-election, beating Green leader Zack Polanski
I would not have voted for Zionism motion, Polanski says
Chris Mason: Questions remain for Green Party leader Zack Polanski
ADHD and autism at risk of over-diagnosis, says report, as author warns of rise in mental ill health
Will El Niño and the polar vortex bring snow to the UK this winter?
Olivia Colman on viral Wicker memes: 'This has never happened to me before'
Weekly quiz: How long did it take for Glastonbury tickets to sell out?
'I don't know what my partner earns': How soon into dating should you reveal your salary?
Russian strikes and approaching winter force many in Kyiv to pack bags and flee
'You're made to feel like a criminal' – cancer survivor screamed at for stoma at airport
Could Christa Pike face execution again and by what method?
US Politics Unspun: Cut through the noise with Anthony Zurcher's newsletter
First look: David Tennant stars in the new series of Time
Find your flow with a peaceful classical soundtrack
New legal drama from the makers of the hit series The Split
How are shells made?
Firing squad execution to be livestreamed, Pentagon says
Emotions run high at the round table as Celebrity Traitors banish two players
£15m spent cleaning illegal waste supersite in ancient woodland
Olivia Colman on viral Wicker memes: 'This has never happened to me before'
'Stark warning' over ADHD and 'Andrew wins legal fight'
I would not have voted for Zionism motion, Polanski says
Suspect linked to Monaco bomb attack on millionaire speaks to BBC
Russian strikes and approaching winter force many in Kyiv to pack bags and flee
'I rage and I don't care': Why women are reclaiming their anger
'I don't know what my partner earns': How soon into dating should you reveal your salary?
Copyright © 2026 BBC. The BBC is not responsible for the content of external sites. Read about our approach to external linking.
About the Author
