Canada’s governor general has described the country’s residential schools as places of unimaginable cruelty, in a eulogy to honour the thousands of Indigenous children who died while attending the institutions. “Today, we make ourselves heard across the country. Although it is hard, we are telling Canadians and the world about our wounds and pain,” Mary Simon, the Queen’s representative in Canada, told hundreds gathered on the grounds of the former Kamloops Indian residential school. A year ago, the Tk’emlúps te Secwépemc First Nation announced the discovery of nearly 200 possible unmarked graves on the grounds. The announcement sent shockwaves through the country, prompting the federal government to establish a national holiday and promise millions of dollars to other Indigenous nations launching their own investigations. Within months, other possible unmarked graves were discovered on the grounds of former residential schools in western Canada, including 751 at the site of the Marieval Indian school in Saskatchewan. Simon, the country’s first Indigenous governor-general, toured the grounds of the former school on Monday to commemorate the traditional end of the mourning period for Le Estcwicwéy̓ – the missing children. Meeting with survivors and community members, Simon nonetheless recognized that many were still grieving. “At this residential school and others like it across the country, churches and governments eradicated Indigenous languages and identity through corrupt policies. They took away our stories,” she said. “It’s unimaginable that a place of learning was so cruel. It’s inexcusable that people could commit these atrocities, or that people could stand silent as they were committed.” Over more than a century, at least 150,000 Indigenous children were forcibly converted to Christianity, given new names and prohibited from speaking their native languages. The last residential school closed in the 1990s. The schools, run by both churches and the federal government, operated by coercion. Canada’s first prime minister, Sir John A MacDonald, told the country’s parliament that an Indigenous child in his or her own community was “simply a savage who can read and write”. In contrast to the welcome for Simon, the prime minister, Justin Trudeau, faced a chilly reception, with a heckling crowd following him around the grounds of the Pow Wow Arbour. “Canada is all Indian land,” a group chanted at him, loudly drumming as he met with attendees. “We don’t need your constitution.” The prime minister said the discovery of unmarked graves had ushered a “difficult year” for Canadians. “This is about remembering who we lost,” he said. “To those who are still filled with hurt and anger, I hear that.” Trudeau had previously turned down an invitation from the Tk’emlúps te Secwépemc to join them in observing Canada’s first-ever National Day of Truth and Reconciliation holiday in September. Instead, the prime minister spent time at a beach resort on Vancouver Island. Kukpi7 (chief) Rosanne Casimir told the crowd that Trudeau “owned” his mistake and had apologized. “He paid his regrets to our unmarked graves. I recognize that as a good start.” She said discovery last year has led to blunt conversations across the country over Canada’s colonial legacy. “The unmarked graves brought truth to the world, and the world stood with us in solidarity,” she said. The discoveries have also brought a wave of contrition from institutions that were largely responsible for the abuses. Earlier this month, the Archbishop of Canterbury, Justin Welby, called the schools a “terrible crime” and apologized for the church’s role. “I am sorry. I am more sorry than I could say. I’m ashamed. I am horrified,” he told survivors from James Smith Cree Nation. His apology follows one from Pope Francis, who met Indigenous delegations in April and lamented the “deplorable” abuses generations of Indigenous peoples faced. Francis is due to visit Canada over the summer, where he is expected to meet with Indigenous groups and once again apologize for the Catholic church’s role in the residential school system. The federal government says it has already released nearly C$80m (US$62m) in funding to nations conducting their own investigations into unmarked graves, including a painstaking search on the grounds of the Mohawk Institute. In her remarks, Simon acknowledged the discoveries over the last year were a reality long suspected by Indigenous communities whose loved ones never returned home . “We mourn with you. We stand with you,” she said. “We believe you.”