Old Chinese, also called Archaic Chinese in older works, is the oldest attested stage of Chinese, and the ancestor of all modern varieties of Chinese. The earliest examples of Chinese are divinatory inscriptions on oracle bones from around 1250 BC, in the Late Shang period. Bronze inscriptions became plentiful during the following Zhou dynasty. The latter part of the Zhou period saw a flowering of literature, including classical works such as the Analects, the Mencius, and the Zuo Zhuan. These works served as models for Literary Chinese (or Classical Chinese), which remained the written standard until the early twentieth century, thus preserving the vocabulary and grammar of late Old Chinese.
Old Chinese was written with several early forms of Chinese characters, including oracle bone, bronze, and seal scripts. Throughout the Old Chinese period, there was a close correspondence between a character and a monosyllabic and monomorphemic word. Although the script is not alphabetic, the majority of characters were created based on phonetic considerations. At first, words that were difficult to represent visually were written using a "borrowed" character for a similar-sounding word (rebus principle). Later on, to reduce ambiguity, new characters were created for these phonetic borrowings by appending a radical that conveys a broad semantic category, resulting in compound xingsheng (phono-semantic) characters. For the earliest attested stage of Old Chinese of the late Shang dynasty, the phonetic information implicit in these xingsheng characters which are grouped into phonetic series, known as the xiesheng series, represents the only direct source of phonological data for reconstructing the language. The corpus of xingsheng characters was greatly expanded in the following Zhou dynasty. In addition, the rhymes of the earliest recorded poems, primarily those of the Classic of Poetry, provide an extensive source of phonological information with respect to syllable finals for the Central Plains dialects during the Western Zhou and Spring and Autumn periods. Similarly, the Chu Ci provides rhyme data for the dialect spoken in the Chu region during the Warring States period. These rhymes, together with clues from the phonetic components of xingsheng characters, allow most characters attested in Old Chinese to be assigned to one of 30 or 31 rhyme groups. For late Old Chinese of the Han period, the modern Southern Min languages, the oldest layer of Sino-Vietnamese vocabulary, and a few early transliterations of foreign proper names, as well as names for non-native flora and fauna, also provide insights into language reconstruction.
