This date was chosen as the statutory holiday for many reasons, including its cultural significance as the Summer solstice, and the fact that it is a day on which many Indigenous peoples and communities traditionally celebrate their heritage.

[6] It was first self-declared Indian Day in 1945, by Jules Sioui[7] and chiefs from across North America.

[6] 21 June was chosen as the date because it often coincides with the summer solstice, a time when many Indigenous groups celebrate their culture.

[12] On 21 June 2017, Canadian Prime Minister Justin Trudeau released a statement pledging to rename the event National Indigenous Peoples Day.

The federal Crown still began using the name National Indigenous People's Day in publications.