50% replacement in MLBA Britain

[Peterski]

Celtic migration, right?

So Scotland_LBA are Celts, I was right about this all along.

[XenophobicPrussian]

He said in "Southern Britain not in Northern Britain so not in Scotland that must reflect we think about a 50% population replacement and then of course there's Saxon movements".

So what population could have caused this? Anyway that is really interesting and it will be interesting if he published more on this.

Urnfield, but not "Celts". Proto-Celts, or part of the Hallstatt/La Tene Celtic ethnogenesis, sure. Nothing before Hallstatt/La Tene is Celtic though. Britain also later received admixture from Hallstatt/La Tene, but it was minor.

[XenophobicPrussian]

Celtic migration, right?

Celts in the Bronze Age, right..

[Peterski]

Celts in the Bronze Age, right..

Yep. Proto-Celtic is older than Proto-Germanic. And the latter also existed in the Bronze Age (Nordic Bronze Age).

Proto-Balto-Slavic also dates back to the Bronze Age (see Balto-Slavic specific genetic drift in Baltic BA samples).

All these major language families date back to the Bronze Age (but not to the Early Bronze Age).

[XenophobicPrussian]

Yep. Proto-Celtic is older than Proto-Germanic. And the latter also existed in the Bronze Age (Nordic Bronze Age).

Proto-Celtic and Hallstatt/La Tene need to be distinguished though, as they are clearly different. Proto-Celtic Urnfield is only one part of the ancestry of Hallstatt/La Tene. Nordic Bronze Age and Iron Age Germanics, not so much, pretty much continuity.

[Peterski]

Proto-Celtic Urnfield

Yes but Urnfield was Proto-Celtic and it brought Celtic languages to the British Isles.

Hallstatt/La Tene were just some distinct sub-groups of Celts, not actual Proto-Celts.

[Peterski]

Britain also later received admixture from Hallstatt/La Tene, but it was minor.

And I doubt that this Hallstatt/La Tene admixture even reached places like Scotland.

It was maybe significant in areas of South England but not all over the British Isles.

Picts/Caledonians probably had ~0% of Hallstatt/La Tene admixture, and were just a mix of British Beakers + Urnfield (which brought their language).

[J. Ketch]

Just to illustrate this, a map made by Mitchellsince1890 on Anthrogenica, of Hallstatt A & B sites, likely representing areas with the greatest early Continental Celtic settlement in Britain. Southern England then had another known influx in the Iron Age from Belgae.

Hallstatt A (1200 – 1050 BC) (fits in the MLBA timeframe)
Hallstatt B (1050 – 800 BC);

Part of the Urnfield Culture, not Hallstatt culture proper.

[Rethel]

Yes but Urnfield was Proto-Celtic and it brought Celtic languages to the British Isles.

Rather Bellbeakers. Later only minor tribes and pots migrated.

[Token]

Good point about the Belgae, so the Southern Britons would have been mostly derived from Continental Celts by the time the Romans met them. It's no wonder then that the Romans made the distinction between the 'Maritime' Southern Britons, who were largely the same as Northern Gauls, and the more native 'Interior' Britons, who sound like they kept up an almost Bronze Age lifestyle by comparison.

This fits linguistic evidence too. Brittonic shares some innovations with Gallic that are absent in Gaelic, such as the shift of PIE roots *qu- to *p- (thus 'P-Celtic'). This made some linguists propose a Gallo-Brittonic branch to the exclusion of Gaelic, but the evidence seems to point more to an areal spread of continental innovations through contact. I'd say the massive Urnfield-Hallstatt A movements brought nuclear Celtic (that is, Celtic preserving the PIE *qu- roots) into Britain. The movement lost its momentum due to struggles with the warlike natives and sheer distance so that the demographic impact was concentrated in the southern parts of Britain (thus the preservation of Bronze age atavisms in Ireland and Scotland as you pointed out). These southern areas more densely settled by Celts preserved contact with the continent through the channel, largely sharing later linguistic (shift to Gallic *p- roots in Brittonic), artistic (Iron age La Tène art for example) and cultural innovations (Celtic roundhouses and hillforts, chariots, etc.) with their continental peers. As evidence of these contacts, besides the tribes with the same names on both sides of the channel there's this famous passage from De Bello Gallico:

The druidic order is supposed to have been created in Britain, and to have been brought over from it into Gaul; and now those who desire to gain a more accurate knowledge of that system generally proceed thither for the purpose of studying it.

I'd say the demographic impact that we will see in Ireland will be sufficient to induce a language shift. Nevertheless the contact with the richer cultures of the continent may have made Celtic a prestige language in Britain (much like Latin throughout the Roman world) and provided additional stimulus to its adoption by the natives. The later shift to *p- from *qu- in southern Britain may have put an end to the common Insular Celtic stage.