Why Buffalo Bills played the Canadian national anthem

There are no Canadian teams in the NFL - but there are millions of fans.

At the Buffalo Bills game in New York on Thursday night, plenty of Canadians wore the team's trademark red, white and blue while drinking beside their pick-up trucks, which were parked to tailgate - a very American pre-game tradition.

The Bills' stadium is only 112 miles (180 km) from Toronto - about a two and a half hour drive for fans - and right across Lake Ontario, which President Donald Trump has sought to rename Lake America.

So it was no surprise that many Canadians arrived long before kick-off to soak up the atmosphere and enjoy the sights of the new Highmark Stadium for their team 's home opener against the Detroit Lions.

What was unusual was that their national anthem rang out through the stadium.

The field was decked out with both the stars and stripes of the US flag and the maple leaf of the Canadian one, and the 1990s Canadian band The Barenaked Ladies belted out Oh Canada! in front of a massive crowd.

It was an emotional moment for many of the Canadian fans, who said they felt an extremely warm welcome even if their country's mood has recently grown more frosty towards the US.

"I've always felt welcome here," said Ben Kerr, from Bradford, Ontario.

"I think it's a nice acknowledgement," he added. "I appreciate that the Bills are doing that for Canada."

The relationship between the two countries, which began to sour when US President Donald Trump returned to office and made repeated calls to annex Canada, has frayed further with an escalating tit-for-tat tariff showdown.

Prime Minister Mark Carney has said Canada, which shares the world's longest undefended border with the US, is "at war" with its southern neighbour over trade. Trump has called Canada "nasty" and "entitled".

Both sides are feeling the economic impact, with Canadian industries reeling from tariffs and Canadians boycotting travel and spending in the US.

The ongoing tensions made the decision to travel to Buffalo a little more complicated for Kerr.

"I try to spend as little money as possible in the US," he told the BBC. "Buy our food in Canada, buy our beer in Canada, bring it across and drink it here. We're not big in supporting the American economy in this trade war."

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Many Americans at the game expressed their own frustrations with the escalating trade war, and the way it has divided the two neighbours.

For Drew Grier, an American who lives eight minutes from the stadium, "the anthem playing tonight is a core part of who we are as a border city".

At a Buffalo Sabres playoff ice hockey game in April, a microphone died while the Canadian anthem was being sung and the audience's voices filled in.

"You sang the Canadian anthem because it needed to happen," Grier said.

Canadian Blake Parnham recalled that moment: "I was sobbing watching the game at home because I felt so vindicated, that Buffalo is different."

He couldn't make it to Buffalo for the Bills home opener, but he enjoyed it from his elaborately decorated backyard in Keswick, Ontario.

Grier said that singing the Canadian anthem tonight is "not that polarising of a thing".

"If anyone is polarising it, it's coming from those outside here, because those of us here, we love Canada," he said.

"The only acceptable reason to sing that anthem would be if they were playing a Canadian team, but they don't play any Canadian teams," posted one fan on social media.

"I don't think it's really necessary," said David Waring, who attended Thursday's game.

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In the end, it may all come down to simple economics.

The Bills' new home, Highmark Stadium, cost $2.2bn to build. While the population of western New York is a little over 1.5 million, the nearby Toronto and Hamilton greater metro areas is home to more than 8 million. Simply put, the team needs Canadian fans.

Gavin Kemp, who has run the NFL-Canada office for eight years, told the BBC that Canada's relationship to the NFL was "extremely important".

Asked why the Bills chose this year to play the Canadian anthem, Kemp said the team was "leaning into one of their biggest parts of their market".

Canada boasts nearly 15 million NFL fans – about one-third of the country's population, and roughly 10-15% of Bills season ticket holders are Canadian, according to the team.

"Sports really transcends all of this," Kemp said. "All this politics is kind of secondary to the fact that your team is doing fantastic right now."

Even American fans who traditionally cheer for other teams found themselves siding with the Bills.

Carol Breed, who backs the Detroit Lions, considered travelling to Highmark Stadium from her home in Battle Creek, Michigan, after she heard they would play the Canadian national anthem.

"I love our country's relationship with Canada," the 74-year-old told the BBC, adding that in Michigan the country is viewed more as a "relative".

"I just hate what Trump has done to the partnership."

She wasn't able to watch the game in person, but has found other ways to scratch her O'Canada itch.

A couple of weeks ago, Breed embarked on the two-hour drive across the border, on the recently opened Gordie Howe International Bridge , which has also stoked divisions between the two nations of late.

"We sang the US anthem until we reached halfway and then started singing the Canadian anthem," she said.

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