From the Canadian Encyclopedia:
“Residential schools were government-sponsored religious schools established to assimilate Indigenous children into Euro-Canadian culture.”
Quite apart from this issue, Macdonald was a colourful character: an alcoholic, he once publicly vomited in the House of Commons, claiming “It’s not drink that makes me sick but the rantings of my honourable opponent!”.
He later ordered the execution of Louis Riel, the leader of a Metis rebellion against Canadian rule, resigned from office due to the Pacific Scandal (he awarded a lucrative railway contract to a construction company from whom he demanded a large sum of money) and was then re-elected Prime Minister.
In the video accompanying the story he is burned in effigy by protesters!
That's only one definition.
An equally valid one, not inconsistent with the original definition posted : Residential schools were government-sponsored schools established to introduce ALL children to the ethics and morals needed to function in modern, civilized societies and cultures.
There is no conflict with the presence or absence of actual religions, except ONE.
Which, to their eternal damnation, our Founding Fathers deemed too unnecessary or too obvious to define.