Jiāngsū was a relative backwater until the Song dynasty (960–1279), when it emerged as an important commercial centre as trading routes were opened up by the Grand Canal. In particular, the south of the province flourished: the towns of Sūzhōu and Yángzhōu played an important role in silk production, overseen by a large mercantile class.

Prosperity continued through the Ming and Qing dynasties, and with the incursion of Westerners into China in the 1840s, southern Jiāngsū opened up to Western influence. During the catastrophic Taiping Rebellion (1851–64), the Taiping established Nánjīng as their quasi-Christian capital, naming it Tiānjīng (天京; Heavenly Capital).

Jiāngsū was also to play a strong political role in the 20th century when Nánjīng was established as the capital by the Nationalist Party until taken over by the communists in 1949, who moved the capital to Běijīng.

Today, proximity to Shànghǎi guarantees southern Jiāngsū a fast-growing economy and rapid development, although northern Jiāngsū still lags behind.