Somebody replied with what happened already, so I will add that this day (Sept 30th) is Canada acknowledging the crimes of the government and church with Truth and hopefully Reconciliation of those events with the Indigenous people..
But heres the Truth: Our government didn't make it a federal holiday, so only some provinces treat it as a holiday where you can go and watch an indigenous celebration. When it was instituted our Premier (Trudeau) was in British Columbia on the Holiday and rather than meet with the Indigenous leaders at a celebration, he went to his island home to chill out. To me this showed exactly how much Canada cared about Reconciliation.