At a ceremony held in the parliament in Ottowa, Mr Trudeau expressed “the government of Canada’s profound regret” for an incident considered one of the most infamous episodes in the country’s history.
In 1864, five Tsilhqot’in chiefs in the province of British Columbia were called to what they thought were peace talks to end what became known as the Chilcotin War.
Instead, they were accused of murdering 14 members of a road-building party.
They were then tried, convicted and hanged, while a sixth chief suffered the same fate later after trying to offer reparations.
In front of their modern-day descendants, Mr Trudeau said: “Today, we come together in the presence of the Tsilhqot’in chiefs, to fully acknowledge the actions of past governments, committed against the Tsilhqot’in people, and to express the government of Canada’s profound regret for those actions.
“We honour and recognise six Tsilhqot’in chiefs – men who were treated and tried as criminals in an era where both the colonial government and the legal process did not respect the inherent rights of the Tsilhqot’in people.”
The Chilcotin War, fought in the midst of the Canadian “gold rush” and a smallpox epidemic that killed at least 14,000 indigenous people, followed rapid expansion of white settlements, often encroaching onto Tsilhqot’in territory.
“As settlers came to the land in the rush for gold, no consideration was given to the needs of the Tsilhqot’in people who were there first. No agreement was made to access their land. No consent was sought,” Mr Trudeau said.
“Some reliable historical accounts indicate that the Tsilhqot’in had been threatened with the spread of the disease by one of the road workers. And so, faced with these threats, the Tsilhqot’in people took action to defend their territory,” he added.
The Tsilhqot’in have long objected to the chiefs being tried as criminals, and Mr Trudeau agreed, saying they had “acted as leaders of a proud and independent nation facing a threat from another nation.”