With the advent of the railways and the ensuing suburbanisation in the late 19th century, Walthamstow experienced a large growth in population and speculative building. From 1894 Walthamstow was an urban district and from 1926 a municipal borough in Essex. In 1931 the population of the borough, covering an area of , peaked at 132,972. In 1965 the borough was abolished and its former area merged with that of the Municipal Borough of Chingford and the Municipal Borough of Leyton to form the London Borough of Waltham Forest in Greater London. Other places in East London formerly of the county of Essex, such as Ilford and Romford were placed into London Boroughs along with Walthamstow. The postal codes for those districts failed to change, however.
One of its most famous residents was the writer, poet, designer and socialist William Morris, who was born there on 24 March 1834, and lived there for several years. His former house in Walthamstow is a museum dedicated to his life and works, while the grounds of the house are a public park (Lloyd Park in Forest Road).
Local engineer, Frederick Bremer, built the first motor car in London between 1892 and 1894. This car is one of the claimants to being the first British built petrol driven car and in 1912 the "Motor" Magazine, after much debate, recognised the Bremer Car as the first British built petrol driven car.
The LGOC X-type and B-type were built at Blackhorse Lane from October 1908 onwards. The B-type is considered one of the first mass-production buses. The manufacturing operation later became AEC, famous as the manufacturer of many of London's buses.
Walthamstow saw lively involvement in the General Strike of 1926, with Winston Churchill's coach reportedly being overturned on Walthamstow High Street. Churchill was also given a hostile reception when he visited Walthamstow Stadium during the general election campaign of 1945.
Walthamstow has three museums: the William Morris Gallery, dedicated to designer and socialist William Morris, the Pump House Museum, which covers transport history, and the Vestry House Museum, the museum of local history. The latter celebrated its 75th anniversary in 2006.
The ancient part of the town, called Walthamstow Village, is a designated conservation area. It centres around St. Mary's Church, which was founded in the 12th century. Across the road from this is a 15th century timber-framed "hall" house which locals have dubbed "The Ancient House". Nearby are almshouses dating from the 16th and 18th centuries, and Vestry House, which has been used as a workhouse and police station, but has been a museum since 1931.
Walthamstow marsh was the location of Alliot Verdon Roe's later attempts to build and fly his early aeroplanes. Despite many failed attempts, Roe continued his experiments and there is now a blue plaque commemorating his first successful flight (in July 1909) on one of the railway arches he worked from. The marsh is now a designated Site of Special Scientific Interest and is one of the last remaining examples of semi-natural wetland in Greater London. Nearby is the Copper Mill. Mills of various types have stood at this location since at least the 14th century, and the current buildings date from the early 19th century. In the mid-19th century the mill was converted to a water pumping station.
The Walthamstow EMD Cinema on Hoe Street, designed by Cecil Masey with fine Art Deco interiors in the Moorish style by Theodore Komisarjevsky and a Christie organ. Originally named the Walthamstow Granada when it opened in 1930, it closed in January 2003 after being bought by the Universal Church of the Kingdom of God (UCKG), which intended transforming it into a church and conference centre. However, their planning application was dismissed in 2003, and the UCKG announced in September 2005 that the cinema would be put up for sale. The cinema is Grade II* listed, however, English Heritage has put the cinema on its Buildings At Risk Register, and has described the overall condition of the cinema as poor. As of October 2007, its future remains uncertain. The McGuffin Film & Television Society is campaigning to restore the cinema to its intended use. This was the only cinema in Walthamstow (indeed, the whole borough of Waltham Forest) at the time of its closure.
Walthamstow greyhound racing stadium - technically in Chingford - was established in 1933 and closed in August 2008 having been run by the Chandler family for the duration of its existence. It reportedly had the largest attendance and income from gambling in the UK. It has a distinctive Art Deco facade, which was given Grade II listed status in 2007. The stadium hosted speedway racing in 1934 and again from 1949 to 1951 when it was the home of the Walthamstow Wolves. Controversy about the sale of the land the track stands on to property developers currently abounds, with a consortium currently trying to buy the stadium back from the developers to continue using the property as a stadium.
The historic central library on the High Street was modernised and expanded in 2006 - 2007, although there were claims that this was at the expense of book holdings. According to the Waltham Forest Guardian, "almost a quarter of a million books have gone missing from Waltham Forest libraries amid claims they have been burned or pulped" and the borough's library stock fell by 60% over the two previous years. At the same time, a large plot at the corner of High Street and Hoe Street was set for substantial redevelopment as a retail space. This site previously contained the town's central Post Office and a shopping arcade, originally built in the 1960s. Plans for the redevelopment of this site fell through in 2005 and are currently in abeyance.
Walthamstow Village conservation area is a peaceful and attractive district to the east of what has become the commercial centre of Walthamstow. The area is roughly defined as being south of Church Hill, west of Shernhall Street, north of Grove Road and east of Hoe Street. Orford Road is the main route through the district, though even this is a quiet thoroughfare by the standards of London. The village has a small selection of specialist shops, pubs and restaurants, and house prices tend to be higher in the streets of this neighbourhood. It was voted best urban village in London by 'Time Out' magazine in 2004.
Upper Walthamstow is to the east of Walthamstow Village. The area's main thoroughfare is Wood Street, which has a good selection of shops and local businesses, and is served by railway, with a station on the Liverpool Street to Chingford line.
Walthamstow has a wide variety of housing stock, but the vast majority of residential property was built in the early 20th century. From Coppermill Lane in the west (next to the marshes), to Wood Street in the east, there are scores of Edwardian and 1920s terraced streets. The area along Markhouse Road and St James Street has many examples of Warner properties. These were developed as affordable housing for the working classes in the early part of the 20th century. Bombing raids in World War II and urban redevelopment projects in the 1960s and 1970s have left areas with more modern housing, mostly in the shape of low-rise concrete blocks.
The northern continuation of Markhouse Road is Blackhorse Road, served by both underground and railway stations, which in turn becomes Blackhorse Lane. This is bound on its western side by industrial units and warehouses. The London Borough of Waltham Forest has proposed developing the area around Blackhorse Road station to become a gateway to the town.
Highams Park and Hale End, though both in the E4 postcode, are historically part of Walthamstow.
Although bounded by the marshes to the west and parts of Epping Forest to the east, there is little open space in the actual town. There were originally two commons in the town, Church Common, adjacent to St. Mary's Church in Walthamstow Village and Markhouse Common, located off Markhouse Lane (now Markhouse Road) and what is now the eastern end of Queens Road. Both open spaces were lost in the 19th century, when the land was sold to property developers.
The artwork for British Band Blur's Parklife album featured photos of the band at Walthamstow Stadium.
Walthamstow was home to the popular 1990s boy band East 17, who named their debut album "Walthamstow" in its honour, the group are also named after the area's postal code E17. Walthamstow is also home to The Bevis Frond.
Walthamstow is a major centre in London's grime music scene, with many bedroom studios and underground music enterprises.
The Bromheads Jacket song "Poppy Bird" references Walthamstow in the chorus.