Norfolk turkey tycoon Bernard Matthews has died at the age of 80, his company has confirmed.
He began his business more than 60 years ago - with 20 eggs and a second-hand incubator.
Mr Matthews, famous for his "bootiful" catchphrase, stepped down from the company's main board of directors in January on his 80th birthday.
Noel Bartram, group chief executive of Bernard Matthews Farms, said Mr Matthews died on Thursday afternoon.
Mr Bartram said: "I have personally known Bernard Matthews for well over 30 years, and on behalf of myself and my fellow colleagues, I wish to express our great sorrow and extend our thoughts and sympathies to the family.
"Rarely has any business been as synonymous with the hard work and values of one man.
"It was Bernard Matthews who grew and developed this company through his entrepreneurial spirit, and clear focus."
Mr Matthews was famous for playing the leading role in his company's adverts, which featured his mansion home.
Lord Sugar wrote on Twitter: "Shame about Bernard Matthews he was a great inspiration to people to show what can be achieved in life by hard work. National Treasure RIP."
The son of a mechanic, he was born in Brooke, Norfolk, in 1930 and left school at 16.
He began his rise to prominence in 1950 when he bought 20 turkey eggs and an incubator at a market in Acle.
By 1952 he was producing 3,000 turkey eggs at his home and moved into poultry farming full-time.
Three years later he bought Great Witchingham Hall, near Norwich - a derelict mansion with 36 acres of land which remains the headquarters of the Bernard Matthews Farms.
The company had suffered some difficult years recently which had included job cuts and an outbreak of bird flu.
When celebrity chef Jamie Oliver launched a crusade to improve school dinners, it was Matthews' Turkey Twizzlers he wanted off plates first.
Mr Bartram said: "In latter years he devoted himself to a host of charitable causes, often in an unsung manner."
These included the independent Caister Lifeboat and the Nelson Museum in Great Yarmouth.
The Sportspark at the University of East Anglia site named its pool after Mr Matthews.
Assistant director of Sportspark Maria Rowe paid tribute and said: "He was a very generous benefactor when we were gathering funding to build the Sportspark.
"He supported us from the start and ensured these excellent sporting facilities were built in Norfolk.
"The Bernard Matthews Olympic pool was named after him in his honour and as a result his legacy will live on."
His death, on the fourth Thursday of November, coincided with US Thanksgiving, often referred to as "Turkey Day".
National Farmers' Union chief poultry adviser Rob Newbery said: "The Bernard Matthews story is an inspiration to any farmer, or entrepreneur.
"Bernard Matthews is a strong rural company, brand and employer, with roots firmly in farming. He created a legacy to be proud of.
Mr Bartram added: "Despite yesterday's very sad news the business will continue to thrive, as we honour his memory through our ongoing work and ensure that the business remains a great British institution, and a key part of the fabric of life in Norfolk and across East Anglia."