How did dialects come into being?

The order of dialect formation (how the original dialect was formed)

The ancient dialect (the earliest dialect) can only be formed because of language differentiation (a language develops independently into different phonetic variants due to social differentiation, without the influence and integration of other languages or phonetics), and there is no integration of language factors.

Modern dialect (the last dialect) was formed in integration of language (the influence and fusion of two or more languages formed the phonetic variation of the language, which was formed by the joint action of two or more languages). In the process of integration of language, it is often merged with the local local language or dialect, thus changing the same language (vocabulary, pronunciation, etc. ), and then the late (modern) dialect came into being. In other words, the bottom of modern dialect is a modern dialect formed on the basis of ancient local languages and through integration of language again.

For example, Jinhua, Yiwu, Dongyang, Pujiang, Pan 'an, Wuyi, Lanxi and other counties and cities in Jiangsu, Zhejiang and Jinhua all have dialects. The bottom of these dialects are dialects formed by the differentiation of ancient local languages. Or how these dialects were formed in ancient times. The answer can only be the differentiation of language. Later (modern), the upper layer of these dialects is what these dialects call modern dialects (modern pronunciation and vocabulary).

Dialect formation order: First, ancient (early) dialects were formed due to language differentiation, and then modern dialects were formed due to integration of language.

-Peking University Chinese Forum: com/viewthread.php？ tid=2 15670