National Aboriginal Day has been observed in Canada since 1996, when the Proclamation Declaring June 21 of Each Year as National Aboriginal Day was declared by the Governor General of Canada, Roméo LeBlanc. One of the recommendations of the 1995 Royal Commission on Aboriginal Peoples (RCAP) was the creation of such a day. Link to a searchable database of the fulltext of the RCAP final report, hearings, and other documents at Library and Archives Canada .
The official version of the proclamation (PC1996-0785) was published as a Statutory Instrument; see the full text of SI/96-55 on the Justice Laws Website or in the Canada Gazette Part 1.
More information about the proclamation the day and can be found on these websites: