Norway's King Harald V has died at the age of 89, after he was taken to hospital last week for treatment for a rare blood condition.
The palace in Oslo said he passed away peacefully at 06:35 local time (04:35 GMT) on Friday at the national hospital in Oslo.
The royal flag on the roof of the palace has been lowered to half-mast and a period of national mourning has been declared leading up to the day of his funeral. Crowds of mourners have streamed to the royal palace to lay flowers and flags.
Harald was the nation's first king born there since the 14th Century. He has been succeeded by his son Haakon, 53, who will hold an extraordinary council of state with the government later on Friday.
King Charles III sent his "most heartfelt condolences" at the death of his "dear cousin" - who was a second cousin to Queen Elizabeth II - while King Carl XVI Gustaf of Sweden remembered "a good friend to me, my family and to Sweden", wishing his godson Haakon "success and good fortune".
After 35 years on the throne, Harald will be remembered as a popular and reforming figure who modernised the monarchy, broke with tradition by marrying a commoner and served as a unifying figure at Norway's most difficult moments.
Royal observers say he was down-to-earth, respected and beloved, describing him as a "grandfather" of the nation and the "People's king" - a title also used by his father King Olav V.
During his reign, the Norwegian monarchy became more egalitarian and transparent about the royal family's finances and health matters, Ole-Jørgen Schulsrud-Hansen, historian and TV2 royal correspondent, told the BBC.
Tove Taalesen, royal correspondent for Nettavisen, described the late king as "one of us", while Caroline Vagle, royal expert for Se og Hør magazine, said he had "always been very close to the people".
"He has never been afraid to show emotion, humour or vulnerability, and that has made him very human."
In the wake of the 2011 bomb and gun attacks on Oslo and the island of Utøya, Harald appealed to Norwegians to support each other and not "let fear take over".
More recently, Harald and his family faced health challenges and scandal, especially over his daughter-in-law Mette-Marit's association with the late sex offender Jeffrey Epstein and her son Marius Borg Høiby's conviction for rape.
He is survived by his wife of almost 58 years, Queen Sonja, their daughter Princess Märtha Louise, their son, the new King Haakon, and six grandchildren.
In the wake of the 2011 bomb and gun attacks on Oslo and the island of Utøya, Harald appealed to Norwegians to support each other and not "let fear take over".
More recently, Harald and his family faced health challenges and scandal, especially over his daughter-in-law Mette-Marit's association with the late sex offender Jeffrey Epstein and her son Marius Borg Høiby's conviction for rape.
He is survived by his wife of almost 58 years, Queen Sonja, their daughter Princess Märtha Louise, their son, the new King Haakon, and six grandchildren.
Harald was born on 21 February 1937 on the Skaugum estate near Oslo. He was three when dictator Adolf Hitler ordered the Nazi German invasion of Norway early in World War Two.
Harald's mother fled with her children across the border to Sweden, and they travelled to the US on the invitation of President Franklin D Roosevelt.
Prince Harald returned with his family to Norway at the end of the war and completed his school and compulsory military service. He became crown prince in 1957, studying social science, history and economics at Balliol College in Oxford from 1960 to 1962.
He met Sonja Haraldsen, the daughter of a businessman, at a party, but the crown prince had to wait nine years before he was allowed to marry her. Eventually he told his father that if he could not marry Sonja, he would stay single, King Harald once told Norway's public broadcaster, external.
His father finally gave his consent and the couple wed in Oslo Cathedral on 29 August 1968.
Harald's choice paved the way for his own two children to marry commoners too, and for Vagle, that "helped bring an end to a very male-dominated royal family".
When his father became ill in 1990, the then-crown prince became regent. Harald then ascended to the throne when Olav died on 17 January 1991.
The new king came into his own around 2000, according to historian Trond Norén Isaksen, growing from a shy man into someone much more open and empathetic.
In July 2011, Harald faced his greatest challenge yet as king, when neo-Nazi Anders Breivik murdered eight people with a car bomb in Oslo before moving onto a youth camp on the island of Utøya, where he shot dead 69 others, most of them teenagers.
He gave a televised address the next day, and weeks later he delivered a speech, empathising with the victims and their families as a father, grandfather, husband and king. On the verge of tears, his voice quivered and broke.
"I can only imagine the depth of your pain. As king of this nation, I feel for each and every one of you," he said.
Looking back, historian Ole-Jørgen Schulsrud-Hansen said: "I think that moment has been burned into our minds of what a monarchy should be."
In 2016, the king made headlines again by giving a, external speech, external supporting diversity of religion, ethnicity and sexual orientation.
He said Norwegians were from "Afghanistan, Pakistan and Poland, from Sweden, Somalia and Syria", that they "believe in God, Allah, the Universe and nothing", and that they "are girls who love girls, boys who love boys, and girls and boys who love each other".
The king was also a keen athlete and environmentalist - one of the initiators of the Norwegian branch of the World Wide Fund for Nature (WWF), who served as president of the Norwegian chapter for 20 years.
He was such an accomplished sailor, he represented Norway three times at the Olympics.
When Crown Prince Haakon married Mette-Marit in 2001, the king and queen welcomed her four-year-old son from a previous relationship. Høiby was treated as one of the family, but the royal house later stressed that he was never a royal.
The king's daughter Princess Märtha Louise initially married a Norwegian writer before controversially remarrying an American self-styled shaman in 2024. The couple's business activities eventually led to her halting her royal duties.
Other polls suggested almost half of Norwegians believed Mette-Marit could no longer become queen, although Haakon is now highly likely to say she will.
However, Vagle said criticism was rarely directed at the late king personally, leaving her with the impression that "everyone has loved King Harald".
"When things go wrong in the royal family, people tend to blame anyone but the king," Isaksen remarked.
Haakon has faced questions about the turbulence surrounding his own household that will "follow him into his position as a king", according to Taalesen, however she believes he has shown leadership and dealt with recent events well.
The royal family's main strategy has been to separate itself from Høiby's trial, and Schulsrud-Hansen believes that has largely succeeded.
Although there may be further scrutiny over the Epstein files, the focus for Norwegians now will be on remembering a "greatly beloved king" and supporting his son.
