Helmshore (/hɛlmˈʃɔːr/) is a village in the Rossendale Valley, Lancashire, England, south of Haslingden between the A56 and the B6235, 16 miles (26 km) north of Manchester. The population at the 2011 census was 5,805. The housing in Helmshore is mixed, with some two-up, two-down terraces, top-and-bottom houses and a few surviving back-to-back cottages. Between the 1970s and 2020 new housing estates have proliferated.

The area around Helmshore is moorland. Post-Ice Age this would have been forested, and bog oak can still be found on the flat peatland tops over 250 metres high. The forest declined in the Neolithic period, and largely disappeared during the Bronze Age, mainly as a result of climatic change although hastened by human activity. There is some evidence of human habitation in the area during the Neolithic period: stone implements found on Bull Hill and in the Musbury valley, and the stones at Thirteen Stone Hill near Grane, and there are a relatively complex network of both local and long-distance old tracks crossing the area.

The village is dominated by the spectacular flat-topped Musbury Tor, once the centre of the medieval hunting park, or Forest. Either side of the Tor are two valleys: Alden Valley in the south-west and Musbury Valley to the north-west. The 'whole land of Musbury' was granted to John de Lacy (before 1241) by Lewis de Bernavill. A licence for a 'free warren' was granted to the Earl of Lincoln in 1294. Work on fencing the Park was completed by 1304–05, with palings being erected. The park, with its 'herbage and agistments' was said to be worth 13s. 4d. in 1311. In 1329 and 1330 it is described as 'Queen Isabel's park of Musbury', and fines were being applied for trespass to, among others, the rector of Bury. Stretches of the ditch enclosure are clearly visible at Grane and Alden valleys, and deer are still occasionally seen in the area. There are several current placenames identifying the Park.

One of the main early tracks that passed through Helmshore was a route from the south (by the Pilgrim's Cross which was in existence in AD 1176) on Holcombe Moor, and then goes through Haslingden on its way to Whalley. This also connected with Watling Street at Affetside, and a well-established way from Bolton to Rossendale. In Anglo-Saxon times, Whalley church was an important Minster and the mother church of an enormous parish. Later, in the medieval period, several chapels-of-ease were attached to Whalley church for the 'ease' of the scattered population providing access to the Mass and the sacraments. After the move made by the Cistercian monks of Stanlow to Whalley at the end of the 13th century, traffic would have increased along this route. In April 2020 the historian Mark Fletcher, in an article 'So Who Were the Medieval Pilgrims?' questioned this theory, and suggested the perhaps rather more plausible alternative that these 'pilgrims routes' were actually used by drovers, moving livestock from grazing areas to markets.

To the south on the old pilgrim road is Robin Hood's Well, and above that is a cairn and memorial stone in memory of Ellen Strange, generally believed to be a young girl murdered by her lover – an event recorded in a Victorian ballad by John Fawcett Skelton but now known to be a murder of a wife by a husband in 1761 that has become replaced by a colourful, but fictional, story. The ballad was commemorated by Bob Frith and Horse and Bamboo Theatre by an event at the site in June 1978, during which a memorial stone carved by Liverpool artist Don McKinlay was unveiled. These routes fell into disuse for anything other than foot traffic after the turnpike improvements of the 19th century.

Helmshore owes its development to a damp climate that was ideally suited to the development of the wool, cotton and linen industries. During the early part of the Industrial Revolution, from the 1790s on, small mills were built on the river valleys, such as Alden Valley where there are still ruins, close to the farming areas – indeed most mill-owners were also farmers. But by the latter half of the 19th century these mills became redundant and industry expanded enormously as mill owners such as the Turner family built terraced dwellings to house the workforce necessary to run their cotton mills close to the roads and railways. During this period Helmshore gradually superseded Musbury as the main name for the community.

Helmshore became a mill workers' settlement, comprising an extensive area of woollen and cotton mills and associated workers' housing built along the valley of the River Ogden. The Turner family first established the settlement, buying land in 1789 and building Higher Mill as a woollen fulling mill powered by two water wheels; later replaced by the one still in existence (now part of the museum). One of the next generation of the family, William Turner (1793-1852) added a larger wool carding and spinning mill, which was steam-powered, in the 1820s. Its chimney is still standing on the opposite hill-side. After a fire in the 1860s the mill was rebuilt, and was later sold to Lawrence Whitaker and his sons in the 1920s. Flaxmoss House on Campion Drive was built as the Turners' residence. Turners also built Tan Pits, a dye works, and the seven-storey, steam-powered Hollin Bank (or Middle Mill) which was built for power looms

The area expanded with the opening of the railway in 1848, and new buildings included the Station Hotel and St Thomas's Church (1851/2). One of the new mill owners who contributed to this expansion was William John Porritt (1820-1896), who was born in Ramsbottom. Porritt worked as a young man at Dearden Clough Mill as a hand-loom weaver and eventually became a cotton merchant. By the standards of the day the Porritts were considered to be good employers. Porritt invested heavily in the new seaside resort of St. Annes, and some of the houses there were built using stone from his Helmshore quarries. He sent workers to see the opening of St. Anne's Pier, organising special trains that ran from Helmshore Station. Porritt mills included the water-powered Bridge End Mill and the huge Sunnybank Mill, which at one time was reputed to have the longest loom in the world. Their mills were famous for industrial felts, some of which were used in the production of bank notes. In 1922 Porritt donated the Memorial Gardens with its clock-tower to the village.