artifacts are introduced to Pit Grave territory. Probable early Satemization. 3000–2500: Late PIE. The Pit Grave culture extends over the entire Pontic steppe (Wave 3). The Corded Ware culture extends from the Rhine to the Volga, corresponding to the latest phase of Indo-European unity, the vast "kurganized" area disintegrating into various independent languages and cultures, still in loose contact enabling the spread of technology and early loans between the groups, except for the Anatolian and Tocharian branches, which are already isolated from these processes. The centum–satem break is probably complete, but the phonetic trends of Satemization remain active. Further expansion during the Bronze Age The Kurgan hypothesis describes the initial spread of Proto-Indo-European during the 5th and 4th millennia BC. As used by Gimbutas, the term "kurganized" implied that the culture could have been spread by no more than small bands who imposed themselves on local people as an elite. This idea of PIE and its daughter languages diffusing east and west without mass movement proved popular with archaeologists in the 1970s (the pots-not-people paradigm). The question of further Indo-Europeanization of Central and Western Europe, Central Asia and Northern India during the Bronze Age is beyond the scope of the Kurgan hypothesis, and far more uncertain than the events of the Copper Age, and subject to some controversy. The rapidly developing fields of archaeogenetics and genetic genealogy since the late 1990s have not only confirmed a migratory pattern out of the Pontic Steppe at the relevant time but also suggest the possibility that the population movement involved was more substantial than earlier anticipated and invasive. Revisions Invasion versus diffusion scenarios (1980s onward) Gimbutas believed that the expansions of the Kurgan culture were a series of essentially-hostile military incursions in which a new warrior culture imposed itself on the peaceful, matrilinear, and matrifocal (but not matriarchal) cultures of "Old Europe" and replaced it with a patriarchal warrior society, a process visible in the appearance of fortified settlements and hillforts and the graves of warrior-chieftains: In her later life, Gimbutas increasingly emphasized the authoritarian nature of this transition from the egalitarian society centered on the nature/earth mother goddess (Gaia) to a patriarchy worshipping the father/sun/weather god (Zeus, Dyaus). J. P. Mallory (in 1989) accepted the Kurgan hypothesis as the de facto standard theory of Indo-European origins, but he distinguished it from an implied "radical" scenario of military invasion. Gimbutas's actual main scenario