A potentially violent end to the Kura-Araxes culture (Alizadeh et al. 2018)

The Kura-Araxes Culture dominated large parts of West Asia during the Early Bronze Age. It's generally accepted that the peoples associated with this archaeological phenomenon were speakers of early Hurra-Urutian dialects, and that they eventually morphed into the Hurrians and other related groups across the northern Near East.

However, it has also been hypothesized that in and around the Caucasus Mountains they were harried and even violently displaced by invaders pushing down from the Pontic-Caspian steppe in Eastern Europe.

A new paper at the AJA Online by Alizadeh et al. explores this angle in detail for a Kura-Araxes site at Nadir Tepesi in the Mughan Steppe, Iranian Azerbaijan, and concludes that it's a very plausible scenario indeed (open access here). Also worth noting in this context, I'd say, is my own recent discovery based on ancient DNA of the rather obvious signals of Yamnaya-related incursions into an area of what is now northwestern Iran not far from the Mughan Steppe (see here). From the paper, emphasis is mine:

By the late fourth to early third millennium B.C.E., Kura-Araxes (Early Transcaucasian) material culture spread from the southern Caucasus throughout much of southwest Asia. The Kura-Araxes settlements declined and ultimately disappeared in almost all the regions in southwest Asia around the middle of the third millennium B.C.E. The transition to the “post–Kura-Araxes” time in the southern Caucasus is one of the most tantalizing subjects in the archaeology of the region. Despite current knowledge on the origins and spread of the Kura-Araxes culture, little is known about the end of this cultural horizon. In this field report, we argue that the Kura-Araxes culture in the western Caspian littoral plain ended abruptly and possibly violently. To demonstrate this, we review the current hypotheses about the end of the Kura-Araxes culture and use results from excavations at Nadir Tepesi in Iranian Azerbaijan.

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Following the decline of the relatively dense distribution of the Kura-Araxes settlements, some striking transformations are reflected in material culture. These include a large reduction in the number of settlements, an increase in burial sites, the appearance of collective burials and impressive royal kurgans, increased mobility, and changes in ceramic traditions (i.e., the appearance of Martkopi-Bedeni ceramics). In addition, there was a clear increase in metalwork, especially in the gold and silver attested mostly in rich burials. [10] To some scholars, all these transformations suggest the arrival of new groups of people with a new lifestyle based on transhumant pastoralism. [11]

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We postulate that around the mid third millennium B.C.E. Nadir Tepesi was abandoned by the Kura-Araxes community. The end of the Kura-Araxes occupation in TTB and TTC is marked by a characteristic red-orange deposit that suggests a large-scale fire. It is unknown whether the destruction covers the whole settlement or is limited to its southwestern portion. However, it is hard to imagine that the fire was accidental since it represents the end of the Kura-Araxes occupation and an abrupt change in the cultural sequence at the site. The last Kura-Araxes occupational layer was immediately followed by a completely different archaeological repertoire. The thick destruction level followed immediately by a decisive break in the material culture suggests a violent end to the Kura-Araxes community at the site.

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Tracing population movement and identifying evidence of migration are major methodological challenges for archaeologists. [49] On one hand, Puturidze argues that there is no evidence supporting the notion of a migration of people into the southern Caucasus. [50] Rather, she associates all the changes in the post–Kura-Araxes period with influences from Near Eastern societies as a result of developing interactions by the end of the third millennium B.C.E. On the other hand, Kohl hypothesizes the possibility of a “push-pull process” [51] in which new groups of people with wheeled carts and oxen-pulled wagons gradually moved from the steppes of the north into the southern Caucasus, and the Kura-Araxes communities subsequently moved farther south. [52]

Kohl also reminds us of the evidence of increased militarism from the Early to the Late Bronze Age that is reflected in more fortified sites, new weaponry, and an iconography of war as seen on the Karashamb Cup. [53] The appearance of defensive mechanisms such as fortification walls, which can be seen at Köhne Shahar, a Kura-Araxes settlement near Chaldran in Iranian Azerbaijan, further emphasizes the increase of inter-group conflicts and militarism during the Early Bronze Age, before the Kura-Araxes culture came to an end. [54] Kohl argues that, while the number of Kura-Araxes settlements decreased in the southern Caucasus, archaeological research indicates that the Kura-Araxes culture spread to western Iran in the Zagros region and to the Levant. [55] In Kohl’s view, as new groups of people moved in, the Kura-Araxes communities abandoned the southern Caucasus and moved farther south, where some of them already resided.

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We believe that the evidence supports a less uniform scenario. The Kura-Araxes culture may have disappeared in various ways; the transition to the post–Kura-Araxes time may not be explained by a single model. Different Kura-Araxes settlements may have ended differently. The evidence from Nadir Tepesi could support a violent end at that site, and it is possible that similar evidence will be found at other sites in the Mughan Steppe. At some sites, such as Köhne Tepesi in the Khoda Afarin Plain, [58] the Kura-Araxes occupation also ended abruptly but without any sign of destruction. In other regions, there may be evidence supporting the coexistence of newcomers with Kura-Araxes communities for some period. [59]

Alizadeh et al., The End of the Kura-Araxes Culture as Seen from Nadir Tepesi in Iranian Azerbaijan, American Journal of Archaeology Vol. 122, No. 3 (July 2018), pp. 463–477, DOI: 10.3764/aja.122.3.0463

See also...

Yamnaya isn't from Iran just like R1a isn't from India