Buyeo (Korean: 부여; Korean pronunciation: [pu.jʌ]; Chinese: 夫餘/扶餘; pinyin: Fūyú/Fúyú), also rendered as Puyŏ or Fuyu, was an ancient kingdom that was centered in northern Manchuria in modern-day northeast China. It had ties to the Yemaek people, who are considered to be the ancestors of modern Koreans. Buyeo is considered a major predecessor of the Korean kingdoms of Goguryeo and Baekje.

According to the Book of the Later Han, Buyeo was initially placed under the jurisdiction of the Xuantu Commandery, one of Four Commanderies of Han in the later Western Han. Buyeo entered into formal diplomatic relations with the Eastern Han dynasty by the mid-1st century AD as an important ally of that empire to check the Xianbei and Goguryeo threats. Jurisdiction of Buyeo was then placed under the Liaodong Commandery of the Eastern Han. After an incapacitating Xianbei invasion in 285, Buyeo was restored with help from the Jin dynasty. This, however, marked the beginning of a period of decline. A second Xianbei invasion in 346 finally destroyed the state excepting remnants in its core region; these survived as vassals of Goguryeo until their final annexation in 494.

Inhabitants of Buyeo included the Yemaek tribe. There are no scholarly consensus on the classification of the languages spoken by the Puyo, with theories including Japonic, Amuric and a separate branch of macro-Tungusic. According to the Records of the Three Kingdoms, the Buyeo language was similar to those of Goguryeo and Ye, and the language of Okjeo was only slightly different from them. Both Goguryeo and Baekje, two of the Three Kingdoms of Korea, considered themselves Buyeo's successors.

The mythical founder of the Buyeo kingdom was Hae Mo-su, the Dongmyeong of Buyeo which literally means Holy King of Buyeo. After its foundation, the son of heaven (Hae Mo-su Korean: 해모수; Hanja: 解慕漱) brought the royal court to his new palace, and he was proclaimed to be King.^{[citation needed]}

Jumong, the founder of Goguryeo, is described as the son of Hae Mo-su and Lady Yuhwa (Korean: 유화부인; Hanja: 柳花夫人) who was the daughter of Habaek (Korean: 하백; Hanja: 河伯), the god of the Amnok River or, according to an alternative interpretation, the sun god Haebak (Korean: 해밝).^{[excessive citations]}

The Buyeo state emerged from the Bronze Age polities of the Xituanshan and Liangquan archaeological cultures in the context of trade with various Chinese polities. In particular was the state of Yan which introduced iron technology to Manchuria and the Korean peninsula after its conquest of Liaodong in the early third century BC.^{[page range too broad]}

In the later Western Han (202 BC – 9 AD), Buyeo established close ties with the Xuantu Commandery, one of Four Commanderies of Han according to the Book of the Later Han volume 85 Treatise on the Dongyi, although it proceeded to becoming a nominal tributary-state and practical ally of Eastern Han in 49 AD. This was advantageous to the Han as an ally in the northeast would curb the threats of the Xianbei in western Manchuria and eastern Mongolia and Goguryeo in the Liaodong region and the northern Korean peninsula. The Buyeo elites also sought this arrangement as it legitimized their rule and gave them better access to Han's prestige trade goods.

During a period of turmoil in China's northeast, Buyeo attacked some of Eastern Han's holdings in 111, but relations were mended in 120 and thus a military alliance was arranged. Two years later, Buyeo sent troops to the Xuantu commandery to prevent it from being destroyed by Goguryeo when it sent reinforcement to break the siege of the commandery seat. In AD 167, Buyeo attacked the Xuantu commandery but was defeated. When Emperor Xian (AD 189 – AD 220) ruled Eastern Han, Buyeo was reclassified as a tributary of the Liaodong Commandery of Han.