The Duke of Edinburgh retired more than three years ago after decades of royal service.
But Philip, 99, kept himself busy, holding audiences, attending royal weddings and meeting new additions to the family.
He survived a car crash early in 2019, emerging unscathed when his vehicle flipped over after colliding with another carrying two women and a baby.
Just before Christmas in 2019, he spent four nights in hospital for treatment relating to a “pre-existing condition”.
Ahead of lockdown, the duke relocated from his cottage on the Sandringham estate to reunite with the Queen at Windsor Castle in HMS Bubble – the nickname given to the couple’s reduced household of staff during the pandemic.
He briefly stepped out of retirement to carry out a rare official public engagement at a military ceremony in Windsor in July 2020.
Here is a look at what he was doing in recent years.
January 17 – The duke is involved in a car crash when the Land Rover Freelander he is driving overturns after hitting another vehicle carrying two women and a baby near the Sandringham estate.
January 19– Photographs emerge of Philip driving a Land Rover without his seat belt on at Sandringham just two days after the crash.
January 27 – It emerges that the duke has written to passenger Emma Fairweather wishing her a “speedy recovery from a very distressing experience”.
February 9 – Buckingham Palace announces that Philip has voluntarily surrendered his driving licence “after careful consideration”.
February 14 – The Crown Prosecution Service confirms that the duke will face no further action in relation to the accident.
April 19 – Philip becomes the third oldest royal in British history, overtaking Princess Alice, Countess of Athlone, who was 97 years and 10 months when she died in 1981.
May 7 – The duke makes a rare appearance at a royal engagement, joining the Queen and broadcaster Sir David Attenborough at a luncheon for Order of Merit members at Windsor Castle.
May 8 – Philip is pictured with his new great-grandson, Archie Mountbatten-Windsor, son of the Duke and Duchess of Sussex.
May 9 – The duke is seen driving a carriage at the Royal Windsor Horse Show.
May 11 – Philip takes his seat in the royal box with the Queen and the Duke of Sussex for the horse show’s pageant event.
May 16 – Philip receives Martin Palmer, secretary general, Alliance of Religions and Conservation, at Windsor Castle.
May 18 – The duke looks in fine form as he attends Lady Gabriella Windsor’s wedding in St George’s Chapel at Windsor Castle.
June 10 – Philip turns 98.
June 21 – The duke holds an audience with General Sir Nicholas Carter, who is relinquishing his appointment as Colonel Commandant of The Rifles.
November 20 – The Queen and Philip reach their 72nd wedding anniversary, spending the day separately, with the monarch in London and the duke at Sandringham. On the same day, the Duke of York steps down from royal duties amid the Epstein scandal.
December 20– The duke is admitted to King Edward VII’s Hospital in central London for treatment relating to a “pre-existing condition”. His stay is described as a “precautionary measure” by Buckingham Palace.
December 24 – Philip leaves hospital after four nights and travels to Sandringham to spend Christmas with the Queen.
March 19 – The duke travels from Sandringham to Windsor Castle to stay with the Queen ahead of the nation going into lockdown during the coronavirus pandemic.
April 20 – In his first major statement since his retirement, Philip praises key workers including refuse and postal staff who have been keeping essential services running.
June 10 – The duke turns 99 and is photographed with the Queen to celebrate the occasion.
July 17 – The duke attends his granddaughter Princess Beatrice’s secret lockdown wedding.
July 22 – In his first official engagement in more than a year, Philip took part in a ceremony at Windsor to hand over his role of Colonel-in-Chief of The Rifles to the Duchess of Cornwall, who was at Highgrove.
The sprightly duke carefully walked down the steps of the castle’s Equerries’ Entrance and joked with one of the soldiers about their fitness levels.
August 4 2020 – The Queen and Philip head to Balmoral for a six-week summer break, followed by a brief stay at Sandringham in September, after which the Queen travels to Windsor in October and Philip stays in Norfolk.
November 2 2020 – Philip returns to Windsor Castle with the Queen, ready for England’s second national lockdown, after the monarch visits Sandringham for the weekend.
November 20 2020 – The Queen and the duke are pictured together to mark their 73rd wedding anniversary, looking at a celebratory card made by the Cambridge children.
December 18 2020 – Philip releases a rare public message praising teachers and school staff for their efforts teaching the nation’s children during the pandemic.
December 25 2020 – The Queen and Philip spend Christmas Day alone, with their staff at Windsor, as the coronavirus crisis escalates.
January 9 2021 – Buckingham Palace announces, during England’s third national lockdown, that the Queen and the duke have received their first Covid-19 vaccinations.
February 16 2021 – The duke is admitted to King Edward VII’s Hospital on a precautionary basis after feeling unwell. Four days later he is visited by the Prince of Wales.
February 23 2021 – The Palace say Philip is being treated for an infection and is “comfortable and responding to treatment”, but is not expected to leave hospital for several days. But it ended up being his longest hospital stay.
March 1 20201 – Philip has successful heart surgery, when he was just three months away from his 100th birthday.
March 16 2021 – The duke is finally discharged from hospital on March 16 – a month after he was first admitted – looking gaunt as he is driven back to Windsor Castle by car to be reunited with the Queen.