I find it very unfortunate that many governments – including ours – do no provide adequate education at the earlier stages of learning to understand both the history and the governance structures – so that the electorate/citizenry can make informed opinions and ensure oversight and accountability from the government. I guess that is why many citizens lack the knowledge.
In short: there is no “one law”. Instead, there is an assortment of both written and unwritten common laws, bills, regulations, and courts – making a legal “system” - such that it is.
I think to start the description of what governance is – is to acknowledge that all humans on this planet can institute whatever governance structure that suits them and their culture. This means that in order to understand how we got here – and what is relevant – is to understand the history of our institutions.
As far as the Western European settler governance legacy goes – obviously one needs to understand how we ended-up with a British Parliamentary system. As far as First Nations goes – one similarly needs to understand their governance structures and history. We need to understand both – in order to understand how the law works – and some of the history of this country that is called “Canada”.
The history of the British Isles/UK starts with the Celtic peoples some 2000-7000 years ago. In terms of laws and governance structures – not much remains today other than the occasional céilidh. Then (in Britain, proper) came the Romans, and they left again (c. 500 ACE). Other than Christianity and the church – not much is left from that occupation. Then the Vikings and Danes – again – not much left for governance (exception: Iceland). Then the Angles and Saxons – and the structure of Kings and monarchy is the legacy there. Then the Normans (c.1066) – quite a bit of law was developed in those times and shortly after – along with the defensive castles that remain today. It is the time of the start of the development of British Common Law (and The Magna Charta and later the English Bill of Rights) – which is the 1st pillar of our current Canadian Parliamentary System (exception: Quebec). Then there is the colonizing of the so-called “new World”, and the country that later would become called “Canada” from ~late 1500s on the East Coast to mid-1750s on the West Coast. The British North American Act of 1867 formalized Canada as a country and later was revised and renames as the Constitution Act. In 1982, The Constitution Act was again revised – and one of the sections (s.35) became instrumental in defining law wrt FN Rights and Title. Out of these Acts – comes Bills passed by Parliament that then become law – each with their own set of Regulations that are subsequently passed through the Governor General after being published in the Gazette. Then there are numerous courts that act as the dispute mechanisms that further define the laws through case law.
As far as FN governance goes – there are many hundreds of separate First “Nations” across Canada – that all had their own governance structures long before the colonists arrived (thanks for that graph, BGM). They started their governance/hereditary systems from ~10,000-14,000 yrs ago. What constitutes what a governance structure has already been ruled on in our courts – as case law. Most of the case law wrt FN governance has been updated since the 1982 repatriation of the Constitution and s.35. However, across this country – there are also a set of Treaties that are still legal and relevant – with the exception of much of the West Coast – where many FN are not covered in Treaties.
So: short version: there is no “one law” - but many. It is complicated, and all humans have a right to the governance structures that make sense to them – as either settlers/colonists – or as FN.