Although archaeological evidence in the Dogon Country was found by Lieutenant Desplagnes in 1907, knowledge of prehistory in the region has long been summarized in a single article published by G. Szumowski in 1956, relating the presence of lithic and ceramic industries in two rock shelters 40 km west of the town of Bandiagara.
In 1988, the geologist M. Burri found a polished axe, a sandstone arrowhead and a few lithic flakes in the Yamé Valley east of Bandiagara. These discoveries motivated a series of field surveys that took place in winter 1993-1994 by Eric Huysecom, now professor and director of the Archaeology and Population in Africa Laboratory (Archéologie et Peuplement de l’Afrique) at the University of Geneva. The discovery of an abundant archaeological record rapidly established that occupations go back to at least the Middle Paleolithic. All of the sites inventories in the surveyed zone are grouped under the term “Ounjougou site complex”, based on the place name where the first finds were recovered.
Located on the Bandiagara Plateau 15 km east of the town of the same name, the Ounjougou site complex includes many sites of different size and nature, distributed within a zone of ca. 10 km² and concentrating around the confluence of the Yamé and three intermittent watercourses. In 1936, a major flood considerably changed the configuration of the watercourse by redesigning its much lower path, leading to strong regressive erosion in the surrounding Quaternary formations. This vertical incision, responsible for spectacular gullies now visible in the area, has created natural sections exceeding 10 meters in height.
The stratigraphic sequence revealed contains many archaeological layers attributable to a broad chronological range extending from the Lower Paleolithic to the present. The Ounjougou sequence is also notable for a series of extremely rich Holocene layers containing well-preserved organic remains (charcoal, pollen, leaves, seeds and wood), offering the opportunity to directly address the relationship between human occupations and climatic and environmental variability throughout a long sequence. To optimally study this unique site in West Africa, the international research program “Human population and palaeoenvironment in Africa” was created in 1997.
Research carried out at the Ounjougou site complex between 1997 and 2004 led to the proposal of an initial scenario for the history of human settlement in the Dogon Country which, however, still contained several archaeological or sedimentary gaps. In 2005, research was progressively expanded to the Bandiagara escarpment and the Séno plain with the view of testing the settlement model defined at Ounjougou and understanding the different gaps shown in the Yamé valley sequence. This second, more extensive, phase of research also focused on linking the settlement history of the Dogon Country with that of neighboring regions. Many Pleistocene and Holocene sites were then discovered. Work in the Dogon Country concluded in 2011 with the second field season at the site of Sadia, an important settlement mound from the pre-Dogon period, dated between the 8th and 13th centuries AD.
Today, researchers involved in the program are also interested in other areas important for understanding the settlement of West Africa. Since 2011, research is conducted in eastern Senegal to restore the archaeological and palaeoenvironmental context of the Falémé valley. An international field archaeology school is also being currently developed in Ivory Coast.