In the Middle Ages the town was an important agricultural producer, with a market charter dating from 1246.
From the 15th to the 17th centuries Wigan specialized in woolen bedding textiles, linen, calicoes and checks.
At its height the Wigan coalfield, centered on just the one district, employed around 30,000 miners, but the smaller, highly faulted seams gradually became unprofitable and worked out, and the coal owners moved on to collieries in other towns such as Leigh, Astley and Tyldesley.

Although Wigan had objected to Charles I  excessive levying of ship money on the town, and democratic feeling was so advanced that the inhabitants were demanding universal male suffrage (Gerrard Winstanley, founder of the Digger movement, was born here), the town remained loyal to the monarchy throughout the Civil War.