His position as head of the Church of England could also spell an historic upheaval as he has previously pondered the possibility of changing his role as "Defender of the Faith" to "Defender of Faith" in recognition of the diverse religions in the modern age. This may be further signalled at his coronation with visible nods to other faiths but will be resisted most rigorously by the Church and the Establishment.
In this and other respects, Charles may be seen as more progressive than his mother. An early adopter of environmentalism, he recalls being considered "rather dotty" for sharing his thoughts. On this, he is more like his father who often corrected references to environmentalism as "conservation".
Charles has stuck to his guns, calling out sceptics with "we all accept what science tells us about everything — until, that is, it comes to climate science".
At COP26 in Glasgow last year, he implored leaders to unite in action. "Our efforts cannot be a series of independent initiatives running in parallel. The scale and scope of the threat we face call for a global systems level solution based on radically transforming our current fossil fuel-based economy to one that is genuinely renewable and sustainable."
He expressed the belief the private sector was ready to work with governments when "the cost of inaction is far greater than the cost of prevention".
While there were some gains at COP26, Charles would have been as disappointed as anyone when the conference failed to deliver the action and commitments needed to reach the targets from the Paris Agreement.
Just as his mother credited Prince Philip as her "stay", Charles will need an ally he can trust. In 2015, he said of the woman who is now Queen Consort: "It's always nice to have somebody on your side... She is an enormous support. The great thing is we laugh a lot because she sees the funny side of life, thank God."
If he is to make the differences he has spoken of so passionately as Prince of Wales, he will need every support of a unified household, and in powerful places.
Could Charles' legacy be tipping the climate catastrophe back in the world's favour? We can hope.
"God Save the King."