Kneeling in front of his mother with his sword at his side, Prince Charles vowed that he would be her ‘liege man of life and limb’ 55 years ago today.

It was a solemn promise that the Prince of Wales – as he was then – would live up to in the decades he spent as the heir of Queen Elizabeth II.

At Caernarfon Castle on July 1, 1969, Charles made history as his mother placed his futuristic coronet on his head while 4,000 invited guests saw the proceedings in person and a further 500million people around the world watched on television.

But the terror threat from Welsh nationalists was so high that the BBC recorded obituary tributes to the 20-year-old future King in case he was assassinated.

In the early hours of the morning of July 1, two militant nationalists were killed by their own bomb in the town of Abergele, on the route of the royal train.

Another bomb planted in a Caernarfon police constable’s garden also went off, and activists hiding in the crowd hurled eggs at the Queen’s horse-drawn carriage.

However, the proceedings were ultimately a success – Charles fulfilled the first part of his destiny and millions across the nation and the world were buoyed by the spectacle.

Kneeling in front of his mother with his sword at his waist, Prince Charles vowed that he would be her ‘liege man of life and limb’ 55 years ago today. Above: The Queen places Charles’ futuristic coronet on his head

Prince Charles poses in his investiture regalia. He was given an amethyst ring (on a band of Welsh gold mined in Gwynedd) to wed him to Wales, a sword representing justice, a gold rod to mark his earthly rule and a mantle of velvet and ermine

In his investiture speech, Charles spoke in both Welsh and English to express his gratitude to the people of Wales and added: ‘It is, indeed, my firm intention to associate myself in word and deed with as much of the life of the Principality as possible – and what a Principality!’

His confident lines in Welsh stemmed from the language lessons he had received during a term spent at Aberystwyth University.

Charles – who took a break from his studies at Cambridge University to receive instruction – was taught by Welsh nationalist academic Dr Tedi Millward.

The pair’s relationship was depicted and Charles’ investiture were depicted in Netflix series The Crown.

Dr Millward, who died in 2020, later refused to attend the investiture ceremony.

But he made enough of an impression on the King for him to issue a tribute when he passed away.

Charles investiture took place in the midst of fierce opposition from Welsh nationalists. Above: An Army bomb disposal van outside Caenarvon Castle the day before the ceremony

In the early hours of the morning of July 1, two militant nationalists were killed by their own bomb in the town of Abergele, on the route of the royal train. Above: The Daily Mail’s report on the blasts

Prince Charles, wearing the gold coronet of the Prince of Wales, looks on at his investiture

King Charles holds his mother’s hand in hers as his father Prince Philip stands just behind them

‘I have very fond memories of my time in Aberystwyth with Dr Millward over 51 years ago,’ he said.

‘While I am afraid I might not have been the best student, I learned an immense amount from him about the Welsh language and about the history of Wales.

‘After all these years, I am forever grateful to him for helping foster my deep and abiding love for Wales, her people and her culture.’

The Daily Mail’s report on the ceremony

That love for Wales was reflected on Charles’ big day.

He was given an amethyst ring (on a band of Welsh gold mined in Gwynedd) to wed him to Wales, a sword representing justice, a gold rod to mark his earthly rule and a mantle of velvet and ermine.

Charles’ specially-made coronet – which was later described by the Queen to Noel Coward as ‘like a candle snuffer’ – was decorated with diamonds in the shape of his star sign.

But the day started with news of the two men who had died when their bomb exploded in Abergele.

The nationalists were from the now-defunct Mudiad Amddiffyn Cymru (MAC), which translates as The Movement for the Defence of Wales.

Two other bombs – including one on Llandudno Pier that was designed to stop the Royal Yacht Britannia from docking – failed to explode.

The man credited with ensuring that Charles’ investiture was remembered for the spectacle itself rather than the danger and controversy that surrounded it was Anthony Armstrong-Jones, the 1st Earl of Snowdon.

As a celebrated photographer, Princess Margaret’s husband ensured the ceremony was television-friendly.

His staging was later praised by the Queen as being ‘spectacular and breathtaking.’

It included a series of convex mirrors that allowed guests stuck behind pillars to see proceedings.

Charles arrived at 2.40pm in an open-top carriage. He entered to the sound of trumpeters of the Household Cavalry sounding from the battlements.

Speaking in Welsh in his speech, Charles said: ‘It is with a certain sense of pride and emotion that I have received these symbols of office, here in this magnificent fortress, where no-one could fail to be stirred by its atmosphere of time-worn grandeur, nor where I myself could be unaware of the long history of Wales in its determination to remain individual and to guard its own particular heritage.

‘A heritage that dates back into the mists of ancient British history, that has produced many brave men, Princes, poets, bards, scholars and more recently, great singers, a very memorable “goon” and eminent film stars.

‘All these people have been inspired in some way by this heritage.’

The nervous Prince was seen on TV tugging at his tunic as he walked to the spot where he would kneel in front of his mother.

The Queen – dressed resplendently in yellow – however betrayed no nerves of her own as she bestowed her son’s insignia of office.

Having laced his hands between hers, Charles said: ‘I, Charles Prince of Wales, do become your liege man of life and limb, and of earthly worship, and faith and truth I will bear unto thee, to live and die against all manner of folks.’

He went on to write in his diary that night: ‘By far the most moving and meaningful moment came when I put my hands between Mummy’s and swore to be her liege man of life and limb and to live and die against all manner of folks.

‘Such magnificent mediaeval, appropriate words.’

The ceremony was sealed with the monarch bestowing the Kiss of Fealty on her son.

Having touched her lips against his left cheek, she then led him out for an appearance on the balcony at Queen Eleanor’s gate.

The Queen and Prince Charles present themselves to crowds at Queen Eleanor’s Gate at Caenarfon Castle

Prince Charles kisses his mother the Queen during his investiture, as his father Prince Philip looks on

The Queen presents her son at the King’s Gate at Canarfon Castle after his investiture

Charles’ specially-made coronet – which was later described by the Queen to Noel Coward as ‘like a candle snuffer’ – was decorated with diamonds in the shape of his star sign

In the sky above, there was a flypast of 12 Phantom and four Lightning aircraft, followed by a carriage procession through the streets of Caernarfon.

The Queen and Charles then retired for dinner on the Royal Yacht Britannia.

Meanwhile, Earl Snowdon and Margaret hosted the official Investiture Ball at the nearby Glynllifon Hall.

It was billed as the Welsh ball of the century, and the star gusts were Richard Burton and Elizabeth Taylor.

Charles then embarked on a four-day solo tour of Wales before returning to Windsor – and ultimately to his studies at Cambridge.

Prince William – who was given the Prince of Wales title by King Charles when the Queen died in September 2022 –  has no plans to have his own investiture.

Kensington Palace said a ceremony is ‘not on the table’.

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