Its territory lay between the states of Qin and Qi and included parts of modern-day Henan, Hebei, Shanxi, and Shandong.

After its capital was moved from Anyi to Daliang (present-day Kaifeng)[2] during the reign of King Hui, Wei was also called Liang (Chinese: 梁; pinyin: Liáng).

[4] Afterwards, "Jin ha[d] no princely house" (晉無公卿) and its political power diffused into extended relations of the ruling family, including the Wei.

In the last years of the Spring and Autumn period, the founders of Wei, Zhao, and Han joined to attack and kill the dominant house of Zhi (知) in 453 BCE, resulting in the partition of Jin.

King Weilie of Zhou finally legitimized the situation in 403 BCE, when he elevated the three houses' heads to the rank of marquess (Chinese: 侯; pinyin: hóu).

The third ruler, King Hui of Wei (reign 369–319 BC), declared himself an independent sovereign and concentrated on economic developments, including irrigation projects at the Yellow River and adoption of Legalist reforms proposed by Li Kui (Chinese: 李悝, c. 459 – c. 395 BCE).

Wei eventually lost the western Hexi (河西) region, a strategic area of pastoral land on the west bank of the Yellow River between the border of modern-day Shanxi and Shaanxi, to Qin.