Milnrow is a suburban town within the Metropolitan Borough of Rochdale. It lies on the River Beal at the foothills of the South Pennines, and forms a continuous urban area with Rochdale. It is 1.9 miles (3.1 km) east of Rochdale town centre, 10.4 miles (16.7 km) north-northeast of Manchester, and spans urban, suburban and rural locations—from Windy Hill in the east to the Rochdale Canal in the west. Milnrow is adjacent to junction 21 of the M62 motorway, and includes the village of Newhey, and hamlets at Tunshill and Ogden.

Historically in Lancashire, Milnrow during the Middle Ages was one of several hamlets in the township of Butterworth and parish of Rochdale. The settlement was named by the Anglo-Saxons, but the Norman conquest of England resulted in its ownership by minor Norman families, such as the Schofields and Cleggs. In the 15th century, their descendants successfully agitated for a chapel of ease by the banks of the River Beal, triggering its development as the main settlement in Butterworth. Milnrow was primarily used for marginal hill farming during the Middle Ages, and its population did not increase much until the dawn of the woollen trade in the 17th century.

With the development of packhorse routes to emerging woollen markets in Yorkshire, the inhabitants of Milnrow adopted the domestic system, supplementing their income by fellmongering and producing flannel in their weavers' cottages. Coal mining and metalworking also flourished in the Early Modern period, and the farmers, colliers and weavers formed a "close-knit population of independent-minded workers". The hamlets of Butterworth coalesced around the commercial and ecclesiastical centre in Milnrow as demand for the area's flannel grew. In the 19th century, the Industrial Revolution supplanted domestic woollen industries and converted the area into a mill town, with cotton spinning as the principal industry. Mass-produced textile goods from Milnrow's cotton mills were exported globally with the arrival of the railway in 1863. The Milnrow Urban District was established in 1894 and was governed by the district council until its abolition in 1974.

Deindustrialisation and suburbanisation occurred throughout the 20th century resulting in the loss of coal mining and cotton spinning. Milnrow was merged in to the Metropolitan Borough of Rochdale in 1974, and has since become suburban to Rochdale. However, the area has retained "a distinct and separate character", and has been described as "the centre of the south Lancashire dialect". John Collier (who wrote under the pseudonym of Tim Bobbin) is acclaimed as an 18th-century caricaturist and satirical poet who produced Lancashire-dialect works during his time as Milnrow's schoolmaster. Rochdale-born poet Edwin Waugh was influenced by Collier's work, and wrote an extensive account of Milnrow during the mid-19th century in a tribute to him.[6] Milnrow has continued to grow in the 21st century, spurred by its connectivity to road, rail and motorway networks. Surviving weavers' cottages are among Milnrow's listed buildings, while the Ellenroad Steam Museum operates as an industrial heritage centre.

Milnrow's historic architecture is chiefly marked by its 18th-century sandstone weavers' cottages, three-storey "fine stone domestic workshops" with mullioned windows. Also known as loomshops or loomhouses, it was estimated in 1982 that Milnrow likely had the greatest concentration of surviving weavers cottages in North West England. A conservation area was created in Ogden in 1974 to protect a range of stables, farm houses and former schoolhouse. Two conservation areas were created in 2006 at Butterworth Hall, covering domestic and municipal buildings respectively in central Milnrow. Former family seats and manor houses - of mostly medieval origin - in the area have included Belfield Hall, Butterworth Hall, Clegg Hall, and Schofield Hall. Belfield Hall, at Milnrow's western boundary with Rochdale, was occupied by a variety of dignitaries, including two High Sheriffs of Lancashire - Alexander Butterworth and Richard Townley. Clegg Hall, at Milnrow's northern boundary with Littleborough, is an early-17th century country house with Grade II* listed building status.

The Grade II listed Church of St James, Milnrow's Anglican parish church, was built in 1869 and is dedicated to James the Apostle. It is part of the Church of England and lies within the Anglican Diocese of Manchester. The origins of the church can be traced to a chantry or oratory built by the Byrons in the year 1400. When that ruling family moved from Milnrow to another of their homes following the Wars of the Roses, the local population was left without a place of worship and a chapel was constructed by the River Beal in 1496 to serve this community. This structure existed until the 1790s, when a "poorly designed" chapel was erected and consecrated; however, due to structural weaknesses, that church was demolished in 1814. Following an interim period when a "plain building" was used for worship, the present church building was built and consecrated by James Fraser, the Bishop of Manchester, on 21 August 1869. Inside, the capitals have foliage decoration sculpted by the "foremost Victorian stonemason" Thomas Earp.

Described as "by far the most distinctive and splendid building in the district", the neo-Gothic Newhey, St Thomas parish church was built in 1876 and served a new Anglican parish of Newhey created in the same year. Dedicated to Thomas the Apostle, it is part of the Church of England, and its patron is the Bishop of Manchester. The church was extensively damaged in an arson attack on 21 December 2007, but later restored in full.

Milnrow War Memorial is located in Milnrow Memorial Park at Newhey, and is a Grade II listed structure. The war memorial was originally sited in central Milnrow, set back from the road near Milnrow Bridge, and was unveiled on 3 August 1924 by Major General Arthur Solly-Flood, a former commander of 42nd (East Lancashire) Division. The memorial is constructed of sandstone surmounted by a bronze statue of a First World War infantryman with rifle and fixed bayonet symbolic of the young manhood of the district in the early days of the First World War. In selecting the design the Milnrow War Memorial Committee was influenced by the statue unveiled at Waterhead in Oldham; the work of George Thomas. Thomas sculpted Milnrow's memorial in 1923. The plinth holds bronze and slate panels recording the names of those who died in the two World Wars.

In Newhey is the Ellenroad Steam Museum, the retained engine house, boiler house, chimney and steam engine of Ellenroad Mill, a former 1892-built cotton mill designed by Sir Philip Stott, 1st Baronet. Now operated as an industrial heritage centre, the mill itself is no longer standing, but the steam engine (the world's largest working steam mill engine) is maintained and steamed once a month by the Ellenroad Trust. The museum has the only fully working cotton mill engine with its original steam-raising plant in the world. Ellenroad Mill produced fine cotton yarn using mule spinning. A 1907-built, working tandem compound condensing engine, made by J. & W. McNaught for Firgrove Mill in Milnrow, is displayed in the Science and Industry Museum in central Manchester.