A website from Indian and Northern Affairs Canada:
This series of maps illustrates the historical evolution of Canada through treaty-making between 1867 and 1999, focussing on the Numbered Treaties. The Numbered Treaties were negotiated between the Dominion of Canada and the First People who inhabited newly-acquired western territories. The maps are available in pdf.
Library and Archives Canada has an online map exhibition called Canada at Scale. There are many maps you may find interesting. In particular:
Note: These maps were published by the Government of Canada in 2004. They may be out of date now. Please use discretion - for informational purposes only.
The Atlas of Canada has an interactive map of the historical treaties signed in Canada. If you click on an area with the information button, there is a link in the popup that will take you to the text of the original treaties.