I'm not familiar with this theory. I have read that the emergence of the
Zarubintsy culture is associated with an eastward migration of people belonging to the
Pomeranian culture into territory occupied by people of the
Milograd culture, and the subsequent mixture between those cultures, which lasted for quite a long time (W. W. Siedow, Седов В. В., Славяние верхнево Поднепровья и Подвинья). The Zarubintsy culture is considered by some scholars Proto-Slavic as it seems to correspond with archaic Slavic hydronymy (Третьяков П. Н., Памятники зарубинецкой культуры). Milograd culture is considered by many scholars Balto-Slavic (before its differentiation into Proto-Slavic, West Baltic and East Baltic) or West Baltic, but Siedow wrote: "В лингвистической литературе высказывались предположения о формировании праславянского на основе одного из окраинных западнобалтийских диалектов или, наоборот, о происхождении западнобалтийских диалектов от одной из групп праславянских говоров." Also Bernstein wrote: "Нет сомнения в том, что балто-славянская сообщность охватила прежде всего праславянский, прусский, ятвяжский язык". So Proto-Slavic and West-Baltic were more closely related than was Proto-Slavic with East Baltic (let's remind you that according to more recent theories, there was no such a thing as a unified Baltic, which later splint into West Baltic and East Baltic - but there was Balto-Slavic which split directly into three branches: West Baltic, Slavic and East Baltic). By the end of the 1st century AD the Zarubintsy culture - according to Siedow - was conquered by Sarmatians, but part of their population escaped northward as refugees and settled in Prussia (archaeological prove of this are supposed to be the type of fibulae which had been previously produced by the Zarubintsy culture, and which start to appear in Prussia in the 2nd century AD). Before that, the Lusatian culture fell to Scythians (see page 76 here:
http://www.parzifal-ev.de/uploads/media/gimbutas.pdf), so most likely the Pomeranian culture - which evolved out of the Lusatian culture (see below) had some Scythian admixture as well.
https://archive.org/details/TheBalts
If we add also your info about contribution of Gubin culture (I guess it contributed more to southern part of that culture than to its northern part), then we have a picture of Proto-Slavs emerging from a mixture of the following archaeological cultures: Milograd (West Balts? or Balto-Slavs?), Pomeranian ("Lusatian" - whoever those Lusatians were - mixed with Scythians) and Gubin (Germano-Celtic Bastarnae?). This would mean that those four peoples contributed to the ethnogenesis of Slavs. So they would be ancestors of Slavs, not some later addition to Slavs. So even if Bastarnae (or maybe Celts who influenced them) originally carried I2a-Din, then still it was part of Slavs since the beginning of their ethnogenesis. A later addition to Slavs - on the other hand - would be Sarmatians, to which the Zarubintsy culture fell by the end of the 1st century AD (according to Siedow). When it comes to the Pomeranian culture:
But it evolved as the result of Scythian influence on the Lusatian culture (see Marija Gimbutas in the link above).
The study by Haak et. al. 2015 found R1a Z280 in an individual of the Lusatian culture from Halberstadt in Germany.
I quoted all the details about that Z280 individual here (what is interesting, that guy was probably a redhead):
http://www.eupedia.com/forum/threads...l=1#post451553
R1a Z280 is today present in all Slavic and Baltic populations in frequencies between ca. 10% and ca. 50% of all males.
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All of this suggests that Proto-Slavs evolved out of an interesting mix of Balts (or Balto-Slavs as they are also called - but Balto-Slavic language was rather more similar to modern Baltic languages than to modern Slavic), Lusatians (maybe they spoke some unknown Indo-European language - Venedic, if such a language existed - some scholars hypothesize the existence of Venedic languages as yet another branch of IE), the Bastarnae or Peucini (Germano-Celtic), Scythians and - the final addition - Sarmatians.
I am probably starting to sound like Germanophiles who see "Germanicness" everywhere. :grin:
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As for the Balto-Slavic past. There are several theories about this:
http://upload.wikimedia.org/wikipedi...ies_Kromer.svg
The graph illustrates several models of Balto-Slavic interactions, trying to explain similarities between the two groups (Schleicher - common ancestral language separating into Baltic and Slavic; Endzelins - two separate languages which came under influence of each other at some point; Rozwadowski - common ancestry, then separation, followed by becoming close neighbours again; Meillet - prolonged close influences despite lack of common ancestry; Kromer - common ancestry with Baltia never constituting a linguistic unity, but East Baltic and West Baltic groups separating directly from Balto-Slavic). Rozwadowski's model is also interesting.
Currently the mostly commonly accepted model when it comes to differentiation of Baltic is this first suggested by Kromer in 2003 - namely that there was no unified Baltic language (from which later West Baltic and East Baltic emerged), but that Balto-Slavic (which, however, was more similar to Baltic than to Slavic) split directly into three parts - West Baltic (now extinct), Slavic and East Baltic.
Here the theories of Schleicher and Endzelins are outlined:
There is also no perfect agreement on when did the separation of Slavic and Baltic (or both Baltic groups) take place.
Proposed dates range from ca. 1500 BCE to ca. 500 BCE (3500 - 2500 years ago):
Atkinson - 1400 BCE
Novotná & Blažek - 1400–1340 BCE
Sergei Starostin - 1210 BCE
Chang et. al. - 600 BCE (
http://www.linguisticsociety.org/fil...AlPreprint.pdf)
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Or maybe something like this:
http://s7.postimg.org/rcznqxcgb/New_Model.png
Except that I2 is Non-Indo-European and Germanic people are Indo-European (despite Non-IE admixtures).
So it can only be Pre-Germanic rather than Germnaic. Or it can be Pre-Slavic.
I1 is also Pre-Germanic (it was probably absorbed by Proto-Germanic Indo-Europeans from LBK culture).