The Duke of Sussex signed off a touching tribute to his grandfather with the Latin phrase Per Mare Per Terram – a motto of the Royal Marines.
Harry described the Duke of Edinburgh, who died aged 99 last week, as “a man of service, honour and great humour” in a statement issued on Monday.
The Duke of Sussex, who has arrived in England from the US ahead of Saturday’s funeral, and Philip have both held the ceremonial title of Captain General of the Royal Marines.
Meaning “By Sea, By Land”, the motto symbolises the Royal Marines’ dual role of fighting both on-board ships and ashore, and is believed to have been used for the first time in 1775 during the American Revolutionary War.
The Duke of Edinburgh had the title for 64 years before it was passed on to Harry in 2017, who held the position for three years – although it was on hold for one year after he quit royal duties.
Such was his passion for the military that, had he not become the Queen’s husband, some believe Philip would have been First Sea Lord, the professional head of the Royal Navy.
Philip joined the Navy after leaving school and in May 1939 enrolled at the Royal Naval College in Dartmouth, where he rose rapidly through the ranks.
His flourishing naval career came to an end in 1951 when he stepped down from his active role in the forces to fulfil his duty as the Queen’s consort when she acceded to the throne the following year.
Former soldier Harry, who served on the front line in Afghanistan, was stripped of his honorary military roles, including Captain General of the Royal Marines, by the Queen in February after he and the Duchess of Sussex confirmed so-called Megxit was permanent.
At the time, a spokesperson for the Sussexes said the couple “remain committed to their duty and service to the UK and around the world”, and believed they could still represent the organisations “regardless of official role”.
Harry quit as a senior working royal last year for a new life in the US with Meghan.
In his tribute to Philip, he said: ““He will be remembered as the longest reigning consort to the monarch, a decorated serviceman, a prince and a duke.
“But to me, like many of you who have lost a loved one or grandparent over the pain of this past year, he was my grandpa: master of the barbecue, legend of banter, and cheeky right till the end.”
Harry is quarantining ahead of Saturday’s funeral at his former home of Frogmore Cottage in the grounds of Windsor Castle, after arriving in the UK over the weekend without his pregnant wife who was advised not to travel.