Students in Saskatchewan donned bright orange shirts Friday in recognition of a dark chapter in Canada’s history.

Orange Shirt Day is marked annually across the country to recognize the harm done to First Nations people who were forced to attend residential schools.

The day was established in 2013, through the efforts of Phyllis Webstad, a First Nations woman who was stripped of her new orange shirt on her first day of residential school in 1973.

"When I got to the (residential) school they stripped me, and took away my clothes, including the orange shirt," Webstad wrote on the official Orange Shirt Day website. Webstad, who was six at the time, was forced to wear an institutional uniform instead.

"The colour orange has always reminded me of that and how my feelings didn't matter, how no one cared and how I felt like I was worth nothing," she wrote.

Regina Mayor Michael Fougere says the day, which was marked in Saskatchewan for the first time Friday, is an important step in the reconciliation and healing process.

“With united voices and collective memories, we as a nation can acknowledge and learn from the past and ensure we pave the way for a future that is free from the trauma and harm created from the residential school system,” Fougere said in a news release.

Oskayak High School in Saskatoon marked the day at its annual fall powwow. Several students and teachers wore orange shirts and staff passed out orange bracelets.

For more than a century, the federal government backed a residential school system that sought to isolate First Nations children from their families and impose on them the dominant Canadian culture. The system was rife with cases of emotional, physical and sexual abuse, giving rise to mental scars that many victims are still struggling to overcome. Others did not survive the system.

The schools were often run as joint ventures between the government and Anglican, Catholic, Presbyterian or United churches.

In 2008, then-prime minister Stephen Harper issued an official apology on behalf of the government for the historic abuses in residential schools, calling it a "sad chapter" in the country's history.

"We recognize that this policy of assimilation was wrong, has caused great harm, and has no place in our country," Harper said.

On Friday, the fourth annual Orange Shirt Day, many Canadians shared their support for the campaign by tweeting photos of themselves in orange. Several echoed the campaign's slogan, "every child matters."

With files from Staff