The reason why Qin and Han dynasties became the common language of official documents in the western regions

The reason why Qin and Han Dynasties became the common language of government official documents in the western regions was mainly because they unified the whole country and used the same language.

Han Dynasty is an important period for the formation and development of a unified multi-ethnic country in China. Since then, titles such as "Han nationality", "Chinese language" and "Chinese characters" have gradually become fixed, and Chinese characters have become the official language of the western regions and one of the earliest languages used by all ethnic groups in the western regions. The widespread use of Chinese in the western region is not only an important way for western nationalities to integrate into the China family, but also a concrete manifestation of their recognition of Chinese culture.