Oral tradition has been recognized by historians as a vital source for historical reconstruction of non-literate societies. However, one of its “deficienc[ies] is an inability to establish and maintain an accurate assessment of the duration of the past [it] seeks to reconstruct.” As a result of its time-lessness it has been declared ahistorical. In the same vein R.A. Sargent argues that

Basically, the concern of critics of oral tradition is that, while they are veritable sources of history, the researcher “must work and rework them with an increasing sophistication and critical sense.” Because dating is very pivotal to the historian's craft, different techniques have been adopted alone or in combination to create a relative chronology. In precolonial African history, the most commonly used have been genealogical data which include dynastic generations, genealogical generations (father-to-son succession) and the age-set generation. Also systematically charted comets, solar eclipses, and droughts have been employed by historians in dating historical events, or in calculating the various generational lengths.

A dynastic generation is determined by “the time elapsing between the accession of the first member of a given generation to hold office and the accession of the first representative of the next.”