The painting by former British Prime Minister Winston Churchill, entitled "The Goldfish Pool at Chartwell" (1962), fetched 357,000 pounds (€402,000, $473,000) at the London auction house Sotheby's on Tuesday. The work, which had never before been seen in public, had been estimated to fetch a price of 50,000-80,000 pounds.

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Another of Churchill's oil paintings also hit the auction bloc as part of Sotheby's sale of modern and post-war British art. "Landscape with two trees" earned a higher price (597,000 pounds), but Sotheby's pointed out that the goldfish painting was remarkable for a number of reasons.

"Unlike many of his landscapes at Chartwell, which focus on a wide panorama of the impressive gardens … the present work is unusual in zooming right into the water itself taking in the luscious foliage along the water side," the auction house said in its description of the dark-hued painting ribboned with warm reds and golds.

Visiting the goldfish pond with his grandchildren was a Sunday ritual for the elderly statesman. He had focused on it as a subject in prior paintings, including in a 1932 work that earned a record-breaking sale sum in 2014.

Influential statesman, Nobel Prize winner — and artist

Churchill (1874-1965), one of Britain's most famous World War-era politicians and winner of the 1953 Nobel Prize in Literature, turned to painting when reached the age of 40. Over more than four decades, he created dozens of works which he never sold but gifted to friends, colleagues and foreign dignitaries.

According to the National Churchill Museum, when asked in 1946 whether he would like to exhibit his paintings, Churchill replied with self-deprecation: "They are not worth it. They are only of interest in having been painted by a notorious character!"

An exhibition of 11 of Churchill's artistic works took place at the Grass House in Lübeck, Germany earlier in 2017.

In 2014, another of Churchill's paintings featuring the goldfish pool at Chartwell was auctioned off. He painted this one in 1932.

The bodyguard behind the 1962 goldfish pond

Churchill created many of his paintings, including "The Goldfish Pond at Chartwell," at his countryside mansion in Kent, a region in southeast England.

The fact that "The Goldfish Pond," painted three years before Churchill died, even exists is thanks to his bodyguard Sergeant Edmund Murray. Murray served the politician in the last 15 years of his life, often setting up the amateur artist's paintbrushes and easels. The bodyguard encouraged Churchill to undertake one final work.

Churchill gifted the painting to Murray upon its completion.