We end at the beginning, when the very idea of English monarchy was established, and when it was almost completely wiped out.
In the ninth century CE, Viking invasions of England had swallowed up most of the petty kingdoms, installing their own puppet rulers or in some instances taking over their own swathes of land.
Alfred was king of the most powerful English kingdom, Wessex, which was the last to hold out against the Vikings. At one point, Alfred was sent on the run by Viking invaders and into hiding … but he later emerged and was able to push the Vikings back until a final defeat forced the invaders to the treaty table. The treaty created the Danelaw, ruled by Vikings, in England’s north, while Alfred in the south was named King of the Anglo-Saxons. He died in 899.
Today he is remembered as Alfred the Great, and traditionally regarded as the first King of England – but had he been a little less canny or lucky in his flight from the invaders, the future of Britain would have been Viking. And maybe the current royal dispute would have to be settled with axes in hand.