On the anniversary of his assassination, we look back on the murder of Louis Mountbatten by the IRA

Now is the best part of a distant half century.

But the explosion that murdered Louis Mountbatten, Prince Philip’s uncle and Prince Charles’ “surrogate grandfather” that day in 1979, still echoes through the years.

The bomb the IRA planted on his fishing boat at Mullaghmore on Carlingford Lough killed Mountbatten, one of his twin grandsons, Nicholas Knatchbull, his stepdaughter Lady Doreen Brabourne and a 15-year-old, Paul Maxwell.

On the same day, a further 18 lives were lost when the IRA ambushed a convoy of British soldiers with two roadside bombs near Warrenpoint.

The bloodshed and the loss of such a close loved one has shaken the royal family to its foundations.

Born as Prince Louis of Battenberg in Windsor in 1900, the son of Prince Louis of Battenberg and Princess Victoria of Hesse was affectionately nicknamed “Dickie”.

His great-grandmother was Queen Victoria, meaning that in addition to his relationship with the late Duke of Edinburgh, he was also a distant cousin of Queen Elizabeth II.

It was also Lord Mountbatten who introduced the young Princess Elizabeth to Prince Philip while the Royal Family were visiting Dartmouth Royal Naval College.

And when Philip had to renounce his title of Prince of Greece to marry Elizabeth, he chose to take his beloved uncle’s surname.

The IRA planted a bomb on Mountbatten’s yacht, Shadow V, while it was moored on Carlingford Lough in 1979. Above: Mountbatten with his family on the same boat

Prince Charles with Lord Mountbatten after watching polo at Smiths Lawn, Windsor

The 79-year-old was a well-known figure in Britain thanks to his close relationship with Queen Philip and his mentee Charles, the Prince of Wales, as he was then.

Mountbatten had also served as head of the Royal Navy and viceroy of India when the country gained independence from Britain in 1947.

He was its first Governor General before returning to Britain a year later. Mountbatten continued his work in the Navy and was appointed the Queen’s personal aide-de-camp in 1954.

The title, awarded to members of the royal family, positioned Mountbatten as an honorary military aide to the Queen.

In August 1979 he was on holiday in Ireland when the IRA planted a bomb on his fishing boat while it was moored overnight in the Irish village of Mullaghmore on Carlingford Lough in County Sligo.

The next morning he set out with his family and a 15-year-old deckhand aboard the distinctive white and green Shadow V.

The group had just reached a set of lobster traps laid the day before when the 50 pounds of plastic explosive hidden in the engine compartment detonated.

The Daily Mail called the day “unprecedented horror in Ireland”.

Dickie, as he was affectionately known, was the last Viceroy of the British Indian Empire.

Prince Charles and Prince Philip chatting with Lord Louis Mountbatten at a polo match in 1977

In a huge explosion, Shadow was shattered. Mountbatten’s grandson Nicholas Knatchbull and teenage crew member Paul Maxwell were killed instantly.

Mountbatten, who survived the initial blast, died while being carried ashore.

The others on board, Patricia, Mountbatten’s daughter, and her husband John Knatchbull; their other son Timothy and Knatchbull’s mother, Doreen, were all seriously injured.

Doreen died the next day, while Patricia would live another 20 years. John Knatchbull died aged 80 in 2005.

Mountbatten shared a close relationship with the royal family. Pictured: Lord Mountbatten, the Queen and Prince Philip saluting from the balcony of Buckingham Palace after the Silver Jubilee procession

Lord Mountbatten on holiday with the Knatchbull twins on the beach below his castle in County Sligo

An Irish policeman examining the rubble of the Shadow V boat that Earl Mountbatten was on when it was blown up by the IRA

Timothy, now 58, who had to manage without his twin brother, was strewn with splinters of wood in the blast and also ended up with a huge black eye.

On the same day as the Mountbatten murder – and not far from it – the IRA also set off two roadside bombs near Warrenpoint which killed 18 soldiers.

It was the deadliest attack on the British Army during the Troubles.

The Daily Mail called the day “unprecedented horror in Ireland”, as the Provisional IRA said it carried out the killings to “bring the attention of the British people to what is happening in Northern Ireland”.

In a sign of the depth of their grief, the royal family observed a week of mourning at court.

The coffin of Lord Louis Mountbatten with the Union Jack flag draped over its top

The Queen and Prince Philip seen at Lord Mountbatten’s funeral at Westminster Abbey

King Charles was very close to Mountbatten, who mentored him as a teenager. Above: The then Prince of Wales at his great-uncle’s funeral

On the day of Mountbatten’s funeral at Westminster Abbey, Charles, who had been his mentor as a teenager, walked behind his great-uncle’s coffin.

According to his wishes, Mountbatten was then buried at Romsey Abbey in Hampshire.

Charles left a wreath of red roses and carnations, with a message that read, “To my HGF and GU from his loving and devoted HGS and GN.”

The words were a family code, with Charles considering his great-uncle Mountbatten his “honorary grandfather”, who in turn had referred to Charles as an “honorary grandson and great-nephew”.