King Arthur's remains are found

Queen Elizabeth II promptly abdicates the throne and renounces any claims the House of Windsor has to it. The descendent of the once and future King are crowned and there is much rejoicing throughout the land.

King Arthur was a Briton, who were named "Welsh" by the Saxons. The House of Windsor was known at this time as the House Saxe-Coburg and Gotha. Windsor came from de-germanizing the name during WWI. The British royal family is German. The English are Anglo-Saxons, which are a German tribe, and are the people King Arthur fought against.
 
As others have said it would be achealogically and anthropologically interesting, but politically irrelevant. HRH Queen Elizabeth II is the most senior legitimate protestant decendant of Sophia of Hanover and thus is the Sovereign by law. Any previous lines are historical and nothing more.
 
party pooper... Who wouldn't want a 21st Century civil war on the isles, True Britianic Welsh vs the Saxon interlopers. The Cornish would have to choose, & no doubt the Scots would sit it out laughing.
 
It would have a major impact on historical study and review of Sub-Roman Britain and the Dark Age period, as well as potentially being used as a political tool for Britain, while also being tied in with the Victorian age of high British patriotism, giving renewed sense to unity and imperialism, which would be a limited in time but a substantial burst with some interesting effects. It would also renew interest in the Middle Ages and Arthur, insofar as the discovery of King Tut had a substantial impact in such a way and Egypt fascination was something defining for its era, which would have a major impact on popular culture for generations and would color books and films and influence creatives and artists.

....We won't cover that whatsoever, and will discuss Queen Victorian assbatting some guy named Bob from Birmingham onto the throne and the Isle of Man declaring itself an anarcho-syndicalist commune, until such point as the thread completely collapses.
 
One huge reason why there would be no change in the monarchy is that Parliament would have to agree to it. This is something that would never happen because if the 1500 year old claim to be High King of the Britons was ruled as valid then Parliament has just declared itself invalid and they therefore have no right to govern, and all laws passed since the death of Arthur are also invalid.
 
To people who are into history, it would be an amazing find. Politically, at most, his descendants demand some sort of Title. Duke something or other most likely

And then another descendent of Arthur's (which is probably the majority of the white British population) sues him and yells, "no, I am the seniormost descendent, therefore it's my title!"

Yeah, no one's getting any peerage out of this.
 
And then another descendent of Arthur's (which is probably the majority of the white British population) sues him and yells, "no, I am the seniormost descendent, therefore it's my title!"

Yeah, no one's getting any peerage out of this.

Very true. If there is one descendant of this "Arthur" there is several millions of them. It is good to remember that all currently living white Brits and so Americans, Canadians, Australians and New Zealanders are all descendants of William the Conqueror who lived centuries after this supposed "Arthur" or whatever his name and title was. Damn, it is possible that all currently living Westerna and Central Europeans are his descendants. We would talk millions if not hundrer of millions people.
 
- Big boost for studies into whatever period Real Arthur was from and general cultural interest in said period. Expect books, shows, etc and probably a Doctor Who episode

- "Arthur" and related names become the 'it' name for babies that year.

- Boost for romantic fantasy fiction in general. ARTHUR REALLY EXISTS!!!! Who cares he's not the mythical one? (GOT-style fantasy probably gets a slump)

- In the context of Brexit, Arthur being real is going to lead to a bit of an upswing in patriotism, optimism, and general swagger in Britain

- Is Arthur definitely Welsh? Expect a big boom for the Welsh nationalists. They'll dine off this.

- Wherever the corpse is gets a lot of tourists for decades to come. Kitschy tourist places will abound. And the UK gets a small short term boost in general tourism.

- No more Arthurian stories as we know them - like, say, palling with the Transformers - because now we know where and when he's from. The Arthur films in preproduction need extensive rewrites.

- Really bad ads for airlines and Visit Britain that use Arthur. Like, really bad.
 
....We won't cover that whatsoever, and will discuss Queen Victorian assbatting some guy named Bob from Birmingham onto the throne and the Isle of Man declaring itself an anarcho-syndicalist commune, until such point as the thread completely collapses.

I tells you the fires of revolution shall sweep the Isle of Man! The Manx proletariat shall overthrow the Tynwald and they shall storm the banks and seize the wealth that the international bourgeoisie have hoarded there, foolishly believing that they had kept it safe from the taxman!
 
As others have pointed out unless there's a whacking great big tombstone with Dux Bellorum Artorus on it what you'll actually get is two days of "Body of Celtic Warlord found. Is this the real Arthur" stories and some very excited archaeology postgrads.
 
We can skip any reference to changes in titles etc. These are in the hands of Parliament (not to mention being politically irrelevant in the 21st century) and not those of aggrieved descendants nor genealogists.

If the Romano-British battle chief's body were found and identified it would have no relevance other to historians, ignorant romantics and to embarrass Hollywood who has been incapable of portraying Arthur other than in a (bad) medieval form of hundreds of years later. It would be amusing to see it done with him speaking in period British to the common people and Latin to his social peers, with English subtitles..........
 
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