Inside Capt. Sir Tom Moore’s Inspiring Life: From Serving in WWII to Being Knighted by the Queen

When Capt. Sir Thomas Moore died this week at the age of 100, he left behind a century of life filled with love, hope, and of course, a dedication to helping others.

The man who captured the world's heart last year after a simple lap around his yard led to more than $40 million raised for the U.K.'s National Health Service was admitted to the hospital on Sunday.

His daughter Hannah Ingram-Moore said he was battling pneumonia after testing positive for COVID-19, and on Tuesday, his death was announced on his official Twitter account.

Though Moore only entered the public eye last spring, his fascinating life story began when he went off to war at 20 years old following an "extremely happy" childhood in Rombalds Moor, West Yorkshire, he wrote in his autobiography Tomorrow Will Be A Good Day.

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Moore enlisted in the 8 DWR (145 RAC) of the British Army as World War II began, and in 1940 was selected for officer training. He served in India and Burma, and following his service, became an instructor in armored warfare, according to his British Army biography.

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"Generally people didn't talk about it," he told the Guardian of war's traumatic aftereffects. "It was something we did and something we got on with and something we came home with. Some people didn't manage to come home."

He married his first wife Billie in 1949, though their 18-year union ended in divorce, according to the BBC.

Moore said he'd come to terms with the fact he'd never find the one — until he met Pamela through work. They went on to marry and welcome two daughters, Lucy and Hannah.

Pamela died in 2006 after a battle with dementia that forced her devastated husband to place her in a facility where she could receive proper care.

"I remember that day well. I had been looking after her at home a long time. But I realized I couldn't do it any longer, that she needed day-to-day assistance," he told British GQ. "I felt I was letting her down. [But] I realize it was the best that could be done. I realize my effort wasn't enough."

In the years after Pamela's death, and as Moore got on in age, he stayed active, driving, mowing his lawn and gardening on his own well into his 90s, until a fall two years ago left him sidelined. He even traveled to India and Nepal on his own to see Mt. Everest, he wrote in his book.

"Life is to be lived and I've always believed that age is no barrier to living it," he wrote.

Moore's second act began on April 5, at an unassuming family barbecue on the first sunny day of the year.

When he took his walker outside to try and do a few laps around the driveway, his daughter Hannah said, "Let's see how many you can manage," while her husband Colin added: "We'll give you one pound per lap, so see if you can do a hundred by your hundredth birthday," Moore recalled in his book.

The teasing challenge turned into a phenomenon that raised millions for the NHS, which Moore felt particularly grateful for after they helped him heal following a fall in his kitchen two years earlier.

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As word of his fundraiser took off, so, too, did the attention: he was featured on the cover of British GQ, became the oldest person to ever achieve a U.K. No. 1 single, had a special stamp released in honor of his 100th birthday and became the first honorary patron of the Imperial War Museum. He also earned the Guinness World Record title for most money raised by an individual through a walk.

He was even knighted by Queen Elizabeth II in July, a moment he reflected on in his book as one he initially "scoffed" at, as he did not feel as though he'd earned the title.

"When Hannah opened the letter and told me the news, I shook my head and cried, 'No! That can't be true!'" he wrote. "I simply couldn't believe it… Despite my incredulity, I was absolutely thrilled that Her Majesty has decided that poor little me should be knighted. It was the greatest honor and something I could never have anticipated."

In addition to the millions of dollars he raised, Moore's legacy will also live on through The Captain Tom Foundation, which he arranged in Pamela's honor.

"I've never been afraid of talking about dying, and I know I'm going to die so I feel no fear," Moore wrote in his book's epilogue. "It comes to us all… I have often thought that when I die all the people I loved the most will be waiting for me."