Many children look up to athletic stars or fictional heroes as role models, but for the United Kingdom's Prince Charles, there was no need: His hero was the flesh-and-blood Louis Mountbatten, 1st Earl Mountbatten of Burma, his father's uncle, the last viceroy of India and first sea lord of the British Navy.

Furthermore, while the dazzling resume and dashing persona made a powerful early impression, the two royals eventually developed a relationship that went far deeper on a personal level, as Lord Mountbatten became arguably the most influential figure in the life of the heir to the British throne.

Lord Mountbatten was a frequent presence in Charles' childhood

As told in Philip Ziegler's biography Mountbatten, Charles first remembered meeting his great-uncle at age 5, when the distinguished commander led the Mediterranean fleet on a showy maneuver past the queen's royal yacht as she arrived in Malta.

Dickie, as he was known to the family, was a natural with Charles and his sister Anne, easily lofting them into the air with his powerful frame and regaling them with tales of his war adventures and travels around the world. While he had grandchildren of his own, he delighted in the presence of Prince Philip and Queen Elizabeth's offspring, with Charles in particular drawn to his elder's infectious enthusiasm.

Along with his frequent presence on family vacations, Uncle Dickie could be depended upon to ensure that royal operations proceeded smoothly, including the time he was tapped to bring Charles, fresh off his 1958 investiture as Prince of Wales, to Wales for the first time under his new title.

A few years later, according to Penny Junor's Charles, when the queen conferred with advisors to chart the course of her oldest child's education, it was Mountbatten's suggestion that won out: "Trinity College like his grandfather, Dartmouth like his father and grandfather, and then to sea in the Royal Navy ending up with a command of his own."

Lord Mountbatten and his wife, Edwina, having a picnic with Prince Charles and Princess Anne on the island of Malta on April 24, 1954

Lord Mountbatten and his wife, Edwina, having a picnic with Prince Charles and Princess Anne on the island of Malta on April 24, 1954

The prince trusted Mountbatten's wisdom and accepted his criticism

By the late 1960s, with Mountbatten in retirement and Charles coming into his own as a young man, the two had forged a tight bond. Charles became a frequent visitor to his "honorary grandpapa's" Broadlands estate in Hampshire, the two enjoying fishing and other outdoor activities before staying up well into the night to discuss history and royal family dynamics.

Devoted to the preservation of the monarchy, Mountbatten wasn't shy about name-dropping the previous Prince of Wales – who abdicated his royal duties in 1936 to marry Wallis Simpson – as a threat to keep his protege in line. Once, when Charles sought to change Easter weekend activities that would have disrupted the family plans of other servicemen, his great-uncle lit into him for his selfishness.

"Of course you were legally right," Mountbatten wrote afterward. "But how unkind and thoughtless – so typical of how your Uncle David started. ... I spent the night worrying whether you would continue on your Uncle David's sad course or take a pull."

While Charles might have chafed at such criticism from his father, his willingness to accept tough words from Uncle Dickie seemingly drew the two men closer. Mountbatten was the only family member to attend the prince's 1971 graduation from the Royal Naval College Dartmouth, and the following year, they shared the somber task of escorting Wallis, Duchess of Windsor, to see her husband's body lying in state in St George's Chapel at Windsor.

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Mountbatten encouraged Charles' romantic rendezvous

With the prince finding himself to be a highly sought-after bachelor during these years, he again leaned on his experienced, cosmopolitan great-uncle for input.

Mountbatten's views on the matter were famously captured in a February 1974 letter to Charles, which read: "I believe, in a case like yours, the man should sow his wild oats and have as many affairs as he can before settling down, but for a wife he should choose a suitable, attractive and sweet-charactered girl before she met anyone else she might fall for. ... I think it is disturbing for women to have experiences if they have to remain on a pedestal after marriage."

The elder's assistance went beyond letters of advice, as Charles was permitted to use Broadlands for trysts beyond the prying eyes of the British press.

Not all of Mountbatten's efforts to steer Charles' romantic interests were successful, as his hope of pairing Charles with his granddaughter, Amanda Knatchbull, never quite got off the ground. Still, the elder royal persisted in trying, and he attempted to arrange a trip to India involving the three of them before fate intervened in the summer of 1979.

Lord Mountbatten and Prince Charles at the coronation of King Birendra in Nepal in 1975

Lord Mountbatten and Prince Charles at the coronation of King Birendra in Nepal in 1975

Charles was devastated by his great-uncle's assassination

That August, Lord Mountbatten was visiting his beloved vacation home in Mullaghmore, Ireland when his fishing boat was blown to pieces by an Irish Republican Army bomb. Mountbatten, his 14-year-old grandson and a 15-year-old boat hand were killed immediately, while another family member died the following day.

Charles, who was vacationing in Iceland at the time, was utterly shocked by the news. He was featured prominently at Mountbatten's ceremonial funeral at Westminster Abbey, reading Psalm 107 to the congregation and television audience, and later delivered a stirring tribute in a memorial service at St. Paul's Cathedral:

"That quality of real moral courage, of being able to face unpleasant tasks that needed to be done – and yet to be fair and consistent – is a rare quality indeed," the prince said. "But he had it in abundance and that, I think, is one of the reasons why people would have followed him into hell, if he had explained the point of such an expedition. ... It is also one of the reasons why I adored him and why so many of us miss him so dreadfully now."

Despite the mostly brave face he attempted to display for these public events, Charles was despondent for a lengthy period as he sought to make sense of life without his most trusted guide. He retreated to Scotland's Balmoral Castle for long walks in solitude and repeatedly watched a BBC video obituary of his honorary grandpa, unable to process the cruel swiftness of his departure.

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The prince recalled Mountbatten's death in a conciliatory speech

Charles eventually recovered from the great loss, in part by following through on the tasks his great-uncle left on his plate. One such responsibility was the stewardship of the United World Colleges, its presidency having passed from Mountbatten to Charles in 1978, and the prince fulfilled one of his predecessor's wishes by launching a branch in the United States in 1982.

In May 2015, Charles obtained a measure of closure by returning to the place where Lord Mountbatten was assassinated, the moment marked by his conciliatory speech that turned a painful memory into a moment of healing, and demonstrated how far the prince had come as a statesman since the days of looking to Uncle Dickie for guidance.

"At the time I could not imagine how we could come to terms with the anguish of such a deep loss, since for me Lord Mountbatten represented the grandfather I never had," the prince said. "Through this experience, I now understand in a profound way the agonies borne by so many others in these islands, of whatever faith, denomination or political tradition. ... Let us, then, endeavor to become the subjects of our history and not its prisoners."