Peter Oakley, perhaps better known as the Internet Grandad - or by his YouTube username Geriatric1927 - has died at the age of 87, a statement on his website said.
His videos were one of the earliest YouTube successes and his channel was the world's most subscribed between August and September 2006.
Mr Oakley's internet career also included his role in the The Zimmers - the self-proclaimed "oldest rock band in Britain" - whose cover of The Who's My Generation reached number 26 in the UK singles chart.
His final video, posted on February 12th this year, ended with the words: "In conclusion I would say my possibly final goodbye. So goodbye."
A short statement posted on askgeriatric.com on March 23rd read:
An earlier post on the same website said Peter had been transferred to a nursing care facility and was "not expected to pull through" from the cancer from which he was suffering.
His account racked up over nine million views in total and his first ever video, entitled 'first try' and posted in August 2006, remains his most popular.
It began with the words: "I've got addicted to YouTube and it's a fascinating place to go to see all the wonderful videos that you young people have produced.
"So I thought I'd have a go at doing one myself."
Describing his approach to YouTube in a video in November last year, he said: "When I first came on to YouTube many years ago now, of course like everybody else I didn't know what to do.
"But because I was elderly, and knowing that all the other people would be younger, I thought it probably a good idea that I talk about life in my young days as compared to life today.
"I did a series called Telling It All and they were very popular."
In March 2013 he wrote for his local paper about his career in the Navy, his passion for motorcycles and his marriage.
"I was 27 when we married," he wrote.
"We had a wonderful life of more than 40 years, without one row. I think it was because she was so tolerant."
And of his cult internet status, he said: "I found I had made contact with young people, those who have looked upon me over the years as a grandad.
"They named me the Internet Grandad. A friend said to me, "that's a bit impertinent" – but no, I replied, I love it.
"It's absolutely amazing. I've done many things because of it."