The article analyzes foreign studies on the history of the 5-10th century, an important period in the history of the Fergana Valley. The scientific significance of the sources of historiography created in English, Russian, French, Turkish and other languages, scientific innovations, shortcomings and their reasons are indicated.

Fergana, Hephthalites, Turkish Khanate, Sassanids, Arab Caliphate, Samanid state, source of historiography.