However, after the Primorsky Krai area was ceded to Russia in 1860, the Qing government began to open the area up to Han Chinese migrants, most of whom came from Shandong. By the beginning of the twentieth century, Han Chinese had become the dominant ethnic group of the region. In 1932, the area was incorporated into Manchukuo, a puppet state set up by Japan, and Changchun (then called Hsinking), capital of Jilin today, was made the capital of Manchukuo. After the defeat of Japan in 1945, the region, together with the rest of northeastern China, was handed to the communists by the Soviet Union. Manchuria was then the staging ground from which the communists eventually conquered the rest of China.

In 1949, Jilin province was smaller, encompassing only the environs of Changchun and Jilin City, and the capital was at Jilin City, while Changchun was a municipality independent from the province. In the 1950s Jilin was expanded to its present borders. During the Cultural Revolution, Jilin was expanded again to include a part of Inner Mongolia, giving it a border with the independent state of Mongolia, though this was later reversed. In recent times Jilin has, together with the rest of heavy industry-based Northeast China, been facing economic difficulties with privatization. This has prompted the central government to undertake a campaign called “Revitalize the Northeast”.