Zhao (surname) in the context of Li (surname 李)

Chinese surnames are used by Han Chinese and Sinicized ethnic groups in Greater China, Korea, Vietnam and among overseas Chinese communities around the world such as Singapore and Malaysia. Written Chinese names begin with surnames, unlike the Western tradition in which surnames are written last. Around 2,000 Han Chinese surnames are currently in use, but the great proportion of Han Chinese people use only a relatively small number of these surnames; 19 surnames are used by around half of the Han Chinese people, while 100 surnames are used by around 87% of the population. A report in 2019 gives the most common Chinese surnames as Wang and Li, each shared by over 100 million people in China. The remaining eight of the top ten most common Chinese surnames are Zhang, Liu, Chen, Yang, Huang, Zhao, Wu and Zhou.

Two distinct types of Chinese surnames existed in ancient China, namely xing (Chinese: 姓; pinyin: xìng) ancestral clan names and shi (Chinese: 氏; pinyin: shì) branch lineage names. Later, the two terms were used interchangeably, and in the present day, xing refers to the surname and shi may refer either the clan or maiden name. The two terms may also be used together as xingshi for family names or surnames. Most Chinese surnames (xing) in current use were originally shi. The earliest xing surname might be matrilinear, but Han Chinese family name has been exclusively patrilineal for a couple of millennia, passing from father to children. This system of patrilineal surnames is unusual in the world in its long period of continuity and depth of written history, and Chinese people may view their surnames as part of their shared kinship and Han Chinese identity. Women do not normally change their surnames upon marriage, except sometimes in places with more western influences such as Hong Kong. Traditionally Chinese surnames have been exogamous in that people tend to marry those with different surnames.

The Tuoba (Chinese) or Tabgatch (Old Turkic: 𐱃𐰉𐰍𐰲, Tabγač), also known by other names, was an influential Xianbei clan in early imperial China. During the Sixteen Kingdoms after the fall of Han and the Three Kingdoms, the Tuoba established and ruled the Dai state in northern China. The dynasty ruled from 310 to 376 and was restored in 386. The same year, the dynasty was renamed Wei, later distinguished in Chinese historiography as the Northern Wei. This powerful state gained control of most of northern China, supporting Buddhism while increasingly sinicizing. As part of this process, in 496, the Emperor Xiaowen changed the imperial clan's surname from Tuoba to Yuan (元). The empire split into Eastern Wei and Western Wei in 535, with the Western Wei's rulers briefly resuming use of the Tuoba name in 554.

A branch of the Tanguts also bore a surname transcribed as Tuoba before their chieftains were given the Chinese surnames Li (李) and Zhao (趙) by the Tang and Song dynasties respectively. Some of these Tangut Tuobas later adopted the surname Weiming (嵬名), with this branch eventually establishing and ruling the Western Xia in northwestern China from 1038 to 1227.

Dai was a state which existed in northern Hebei during the Spring and Autumn period of Chinese history. Its eponymous capital was located north of the Zhou Kingdom in what is now Yu County. It was apparently established by the people known to the ancient Chinese as the Baidi or "White Barbarians". They traded livestock and other goods between Central Asia and the Zhou states prior to their conquest by the Zhao clan of Jin.