I think the history of early Britain was obscured by that: obscurity.
The incident that changed the world in the 700s BC and lasted up to the beginnings of 1000's AC is the reason why the transmission of the events was mixed with fables to become legends that endure up to today.
In my opinion, in order to understand the history of Britain, one must collect the pieces of evidence scattered here and there and start to connect the dots forming the figure.
British is a word that means "the man of (the) covenant". Question will be: a covenant with whom?
The legend of King Arthur talks of the right person to insert the spade into the stone. Second question then is: what stone are they talking about?
And so forth. This is to say, better start playing the game with the loose pieces and start to make them joint properly.
I will do what is forbidden in traditional, but the case of King Arthur still is catalogued as "legend". This is the game to play.
Why not starting with information obtained from sources which in appearance have nothing related to the subject itself.
The Bible mentions of a dude called Jacob, a very tricky man since he was born. I won't speculate anything but just describe some events happening with this dude. In one moment when he was traveling, he collected some stones and forming a pillow he went to sleep. He had a dream, a weird dream. When he woke up, he was excited. (original Hebrew mentions "stones" but later Jacob lifted one stone only. Someone suggested that a miracle happened, and the stones became one. This part could be Hebrew idiomatic term, or the way they talked in those times, but is not much important to get deep into "stones" and "stone" at this time).
The case is that he appears to call "Bethel" to the place that is called Luz. He carried that stone with him, poured it with oil. Jacob made a pillar, and the "stone" was put at the top, in other words, he made an altar.
Even when the Bible doesn't specify it, Jacob took and carried that "stone": with him wherever he went to. Years passed by and now Jacob is very old and blind in Egypt, and he called his children. Before dying he decided to bless his sons. Before assembling with all of them, he called Joseph and his sons Ephraim and Manasseh, and he told them the story of the Almighty appearing to him in the land Called Luz, about the received blessings, etc. Later, when all his children were together with him, Jacob started to give blessing to them.
When it was Joseph's turn, Jacob gave him a particular "gift". Most translations don't appreciate much what the Hebrew text says, but to give it a proper meaning, Jacob said the following: "
But his bow remained steady, his strong arms stayed limber, because of the hand of the Mighty One of Jacob, because of the Shepherd* "of" the Rock of Israel. (* shepherd, keeper).
Joseph became the keeper of Bethel, the Rock of Israel.
Joseph asked his sons to bring his bones with them wherever they went to, apparently Joseph didn't want his rest to stay in Egypt. When The Arc was built, the rests of Joseph were carried near it, but the "stone" was also inside Joseph's coffin. The Exodus, the creation of the Kingdom of Israel, the split of this kingdom in two, the invasions of the Egyptians and finally of the Chaldeans/Babylonians. Zedekiah became the last king of Judah and the exile to Babylon was next. After receiving his freedom, according to 2 Macabees, Jeremiah took the Ark to the mount where Moses was allowed to give a look at the promise land. From here Jermiah traveled to the isles of the West. His arrival was first to Ireland. Here in Ireland was born a legend of a man who arrived with a wonderful stone. Other legends were born around the "stone", that Druids took it with them, and between a century the "stone" ended in Scottland. The "stone" continued being sacred all the way from Babylon/Judah up to Scottland.
As far as the legend goes, the final destiny for this "stone" is Westminster Abbey. According to the legends, no matter where the "stone" ends its whereabouts, always a Scottland king will be the ruler of that place.
Here is where I find the similitud between the stone of the King Arthur legend coinciding with the legends about the "Stone of Israel": only the right person might be the ruler when put his hands on that stone. It must be noticed that when old prophet Jeremiah arrived at Ireland, he found descendants of king David, and that these descendants took care of that "stone".
Just legends...
