Inscriptions on tomb steles (mubei 墓碑) were a traditional way of commemorating the career, achievements, and virtue of high-standing persons in ancient China. Epitaphs (mubei wen 墓碑文) had thus biographical functions. Moreover, many of them were composed (yu mu 諛墓) by excellent literati and writers, and are therefore also examples of literature of high quality. A third purpose of tomb inscriptions is the presentation of beautiful calligraphy. For this reason, tomb inscriptions were often studied by scholars interested in arts and writing styles.
There were basically two types of tomb steles, namely such erected vertically, either directly at a tomb (mubei, mujie 墓碣, mubiao 墓表), or along the "soul path" (shendao bei 神道碑), and such placed in lower positions or even dug into the earth. The latter bore inscriptions called muzhiming 墓志銘. While tomb steles (mubei) were used for high-ranking persons, state officials of rank 4 and lower were only granted smaller tablets (mujie). While commoners without official position were only granted tomb inscriptions of the type mubiao, the latter term could also be used for mubei or mujie. It particularly refers to inscriptions placed in front of a tomb.
Tomb steles were introduced during the Han period 漢 (206 BCE-220 CE), but they were derived from wooden plates used to lower the coffin into the grave. The glossary Shiming 釋名 explains the word bei 碑 as "to cover" (bei 被) and says that in old times, these wooden board were already inscribed with laudatory information on the deceased person.
Examples for famous inscriptions are Han Yu's 韓愈 (768-824) Tang guxiang Quan gong mubei 唐故相權公墓碑, Wang Anshi's 王安石 (1021-1086) Guangxi zhuanyunshi Sun jun mubei 廣西轉運使孫君墓碑 or Zhang Pu's 張溥 (1602-1641) Wu ren mubei ji 五人墓碑記. Inscriptions used both prose (wen 文) and rhythmic sentences (ming 銘), and some even had an introduction (xu 序). The rhythmic part (ming) was written like a poem, in verses, and sometimes also with rhymes, as a kind of summarizing eulogy.
Even if the rule was that tomb steles had a square top, this is not the case for all of them. Steles of high-ranking person were often decorated with patterns or pictures. The title was written in seal script (zhuan'e 篆額 "seal-script front"), while the body of the inscription was written in the style of chancery script.
Because tomb steles were used for high-ranking persons, the erection of them had to be allowed by the court, at least during the Tang period 唐 (618-907).