Winston Churchill is best known as the bullish British prime minister who guided his country through the Second World War and changed the course of modern history. But aside from being an outspoken statesman, Churchill was also a painter with an eye for sweeping landscapes and big skies.

Naturally, those artistic tendencies drew Churchill to the Rocky Mountains. In 1929, the British politician vacationed at Emerald Lake in B.C., about 200 kilometres west of Calgary, where he captured the turquoise waters and snow-capped mountains in an oil painting.

After years in a private collection, the artwork -- now weathered from age -- is headed to auction in London next week, where it’s expected to catch between $10,000 and $13,000.

Churchill’s paintings have gone up for auction before, often drawing plenty of attention from collectors. But the art world wasn’t even aware that the Emerald Lake piece existed until recently, according to Frances Christie, a senior director with Sotheby’s.

“He painted a few scenes, there’s not very many known, but we hadn’t realized that he’s painted Emerald Lake until this picture surfaced onto the market,” Christie told CTV News.

During a month-long trip to Canada, Churchill was enchanted by the lake and set up his easel near the shore one summer day. Canadian historian David Finch said Churchill was smitten with the view.

“He just loved it and he said to his wife, 'I want to bring you back here, to this specific spot,’” Finch said.

Years after completing the piece, Churchill’s bodyguard Sgt. Edmund Murray asked his boss if he could keep it. Churchill said yes.

Murray’s children eventually inherited the painting and kept it for years in the privacy of their home. But, recently, they decided they wanted to share the painting with the world.

“It is very special,” said Bill Murray, Sgt. Murray’s son.

But deciphering the story behind the painting took some local expertise. At first, the painting was mistaken for nearby Lake Louise, which also has distinctively blue-green waters. In fact, Churchill had written “Lake Louise, Canada” on the painting’s bottom left corner.

But Finch, who is well versed in the region, helped the family realize the artwork’s true origin.

“I said I don't want to tell you your business but this isn't Lake Louise, this is Emerald Lake. So then I gave him a photograph from the same perspective,” he said.

The sale comes at a time of renewed interest in Churchill in pop culture. Gary Oldman recently won an Oscar portraying the British leader in “Darkest Hour.”

Sgt. Murray’s family has said they hope the piece will be sold to a Canadian collector. The piece will go up for sale March 20 through Sotheby’s of London.

Today, Emerald Lake is a popular tourist destination tucked within Yoho National Park.

With files from CTV’s Alberta Bureau Chief Janet Dirks