Aboriginal adoptees forced from their families by the Canadian government in the Sixties Scoop are expected to receive what is believed to be the first public government apology on Thursday.

Manitoba Premier Greg Selinger is set to deliver the apology, which the province has been working on for months alongside affected adoptees.

The Sixties Scoop is the name given to the period of time between the 1960s and '80s when thousands of aboriginal children were placed with mostly non-native adoptive families.

I remember my uncle crying, I remember him packing a suitcase, and hugging me and kissing me goodbye. - Marlene Orgeron, adopted during Sixties Scoop

It's believed somewhere between 11,000 and 20,000 aboriginal children were removed from their homes and placed with new families in Canada, the U.S. and Europe.

Some estimate more than 20,000 aboriginal children were relocated.

The estimates vary greatly because many aboriginal children are believed to have not been recorded as status Indian in their child services records.

Adoptee Marlene Orgeron remembers being forced to leave her uncle's home along with her two brothers when she was three years old. The sibling trio was adopted by a non-aboriginal family in New Orleans, La.

"I remember my uncle crying, I remember him packing a suitcase, and hugging me and kissing me goodbye," she says.

Formal apology, recognition demanded

Many adoptees under the program have been demanding a formal apology from the government.

"This has been swept under the rug," says Coleen Rajotte, who was adopted out as a baby. She's been advocating for former adoptees to be recognized for years, and is among the ones demanding an apology.

Aboriginal residential school survivors have already received a formal apology from the Canadian government. In 2008, Prime Minister Stephen Harper apologized for the harm done to aboriginal children and their communities by the government when it removed children from their families and placed them in "far too often" abusive and neglectful residential schools.

"I stand before you, in this chamber so central to our life as a country, to apologize to aboriginal peoples for Canada's role in the Indian residential schools system," he said at the time.

Marlene Orgeron

Marlene Orgeron was taken from her Manitoba home when she was three years old. She was sent to an adoptive family in the U.S. (CBC)

Residential school survivors were also able to speak at hearings held by the Truth and Reconciliation Commission, which recently released its findings.

The commission mentions victims of the Sixties Scoop in a summary of its final report, saying "the promise of reconciliation, which seemed so imminent back in 2008 when the prime minister, on behalf of all Canadians, apologized to survivors, has faded."

Those adopted during the Sixties Scoop have yet to be formally recognized.

"We lost our language. We lost our connection to our home communities... We were victims of colonization and Canadians need to recognize that this is a part of our history," says Rajotte.

The province of Manitoba had some of the highest numbers of aboriginal kids taken away from their homes. Between 1971 and 1981, more than 3,400 Manitoba aboriginal children were sent to adoptive or foster families, according to the province's Aboriginal Justice Inquiry.

Since Manitoba's aboriginal people were so widely impacted, Premier Selinger says it's appropriate the province be among the first to apologize.

He says he hopes the apology prompts the federal government to follow suit.

Class-action lawsuits

In addition to a formal apology, many of the people who were taken from their homes during the Sixties Scoop are seeking monetary compensation from the federal government.

Class-action lawsuits have been filed in Ontario, Manitoba, Saskatchewan, Alberta and B.C.

This year, a Saskatchewan law firm filed a class-action lawsuit against the federal government representing plaintiffs from a number of provinces. More than 1,800 people have signed on as plaintiffs.

In 2009, Marcia Brown Martel and Robert Commenda launched a class-action lawsuit representing Ontario victims against the Attorney General of Canada. The suit was approved by an Ontario judge, but the Canadian government appealed that decision. The Ontario Superior Court dismissed the government's appeal in late 2014.

Another plaintiff has brought forward a class-action lawsuit representing victims who lived in B.C. when they were adopted out.

With files from the Canadian Press