He assumes his new role at a difficult time, as the royal family has faced health challenges and scandals this year.
Mette-Marit came under scrutiny when it was revealed that she had had a three-year friendship with the late convicted sex offender Jeffrey Epstein, for which she publicly apologised.
She later received a lung transplant, after suffering from pulmonary fibrosis since 2018. Doctors will not declare her stable until next year, meaning her husband must balance his new official duties with her care.
Her son from a previous relationship, Marius Borg Høiby, was convicted in June of rape and other offences and sentenced to four years in prison. He is appealing.
Høiby is not a member of the royal family, but was raised with them since he was four years old, when Haakon married his mother.
Haakon’s sister, Märtha Louise, has also courted controversy for remarrying an American self-styled shaman in 2024, their business activities ultimately leading her to step back from royal duties.
Without directly referencing these controversies, Haakon said during his speech: “Our family has experienced the importance of standing together in order to remain steadfast both within ourselves and for one another even during difficult times.”
He said he, along with Mette-Marit and Crown Princess Ingrid Alexandra, would “always strive to understand the life situations of different people”.
He added: “No one who lives in this country knows what we will face together, but what we do know is that we will stand by one another through both good days and difficult ones.”
Although Harald remained popular until his death, a poll for newspaper Aftenposten earlier this year suggested that support for the monarchy had dropped from 72% in 2024 to 54%.
However, Norwegian royal experts told the BBC that the new king, while facing questions about the turbulence surrounding his family, was respected, hard-working and, they believed, able to move forward despite the challenges.
