St Helens is in the south west of the historic county of Lancashire, 6 miles (10 km) north of the River Mersey. The town historically lay within the ancient Lancashire division of West Derby known as a "hundred". Incorporated as a municipal borough in 1868, and responsible for the administration of the townships of Eccleston, Parr, Sutton and Windle, it became a county borough in 1887 and a metropolitan borough in 1974.
The area developed rapidly in the Industrial Revolution of the 18th and 19th centuries into a significant centre for coal mining and glassmaking. It was also home to a cotton and linen industry (notably sail making) that lasted until the mid-19th century as well as salt, lime and alkali pits, copper smelting, and brewing.
Glass producer Pilkington is the town's only remaining large industrial employer. Previously it was home to Beechams, the Gamble Alkali Works, Ravenhead glass, United Glass Bottles, Triplex, Daglish Foundry, and Greenall's brewery.
The southern part of what became the traditional county of Lancashire was at least partially settled by the Brigantes, a Celtic tribe, who were subjugated by the Romans during their 1st Century conquest, with nearby Wigan suggested as a location for the Roman settlement of Coccium. Eccleston in St Helens appears to derive its name from either the Latin ecclesia or the Welsh eglwys, both meaning "church", suggesting a common link to a place of worship although none is known in that township until the 19th century.
The first recorded settlements are the Manors, Parishes and Titled Lands listed in the Domesday Book in the 11th century. The titled lands would have encompassed the modern townships of Sutton, Windle and Parr as part of their fiefdoms, though it may be inferred from the listed tithes that the land was populated before then.