Before Mandarin
Since ancient history, the Chinese language has always consisted of a wide variety of dialects; hence prestige dialects and linguae francae have always been needed. Confucius, for example, used yǎyán (雅言), or "elegant speech", rather than colloquial regional dialects; text during the Han Dynasty also referred to tōngyǔ (通語), or "common language". Rime books, which were written since the Southern and Northern Dynasties, may also have reflected one or more systems of standard pronunciation during those times. However, all of these standard dialects were probably unknown outside the educated elite; even among the elite, pronunciations may have been very different, as the unifying factor of all Chinese dialects, Classical Chinese, was a written standard, not a spoken one.
Read more about this topic: History Of Modern Standard Chinese