Objective. Explanation of the late stages of glottogenesis (ordering of an utterance parts, the formation of full-fledged words from protowords, the appearance of the first syntax and grammar constructions) by means of theoretical reconstruction of social orders, challenges, communicative concerns, and practices of late erectus (proto-sapiens and early sapiens) based on indirect data, general laws of social psychology, individual and group behavior. Background. The research on the origin and evolution of language is being actively carried out in last decades. Special educational and research programs, laboratories, centers, societies, journal headings are multiplying; there are even magazines and whole book series devoted to this topic. This interest is determined by the fact that the origins of the main human features and merits such as consciousness, culture, thinking, cognition, are inextricably linked with the origin of language. In the last 10—15 years, attention has been growing to socio-psychological and paleo-sociological explanations of glottogenesis processes. This article develops this direction considering the achievements of domestic science, first the theoretical legacy of Leo Vygotsky. Methodology. An evolutionary approach with usage of multilevel selection mechanisms. Paleo-anthropological, paleo-psychological, and paleo-sociological reconstructions. Conclusions. The transition from the early stages of articulate speech to a proto-language and a full-fledged language was a multi-stage process of complexity and accuracy of utterances increasing. It was a response to step by step renewed techno-natural niches, social orders, and communicative concerns of proto-sapiens, and then early sapiens. The main role was played by the development of fire, collective cooking, joint meals, and the associated ritual practices of telling stories about events that occurred. The result was practice of distant normative control that led to further development language precision and complexity. In later stages, due to environmental and demographic factors in southern and eastern Africa, forced migrations and frequent intergroup clashes led not only to conflicts, but also to the formation of alliances. This formation required negotiations with higher levels of accuracy, logical consistency, and abstractness of communication.