During the development of the Isle of Dogs the street signs pointed to the new development (by the LDDC), and Poplar was lost for a decade or more. St Matthias Old Church is located on Poplar High Street, opposite Tower Hamlets College. It is next to Poplar Town Hall - which has mosaic detail - and Poplar Bowls Club, which is part of Poplar Recreation Ground. A recently re-opened sports centre called The Workhouse stands on the site of Poplar Workhouse, where local politician Will Crooks spent some of his earliest years (a nearby council housing estate is named after him).
On June 13, 1917, German Gotha G carried out the deadliest German raid on London during World War I. One of the bombs fell on a nursery school in Poplar, causing the death of forty-six children - a tragedy which shocked the British public at the time .
The Metropolitan Borough of Poplar was the location, in 1921, of the Poplar Rates Rebellion, led by George Lansbury. As part of the 1951 Festival of Britain, a new council housing estate was built to the north of the East India Dock Road and named the Lansbury Estate after George Lansbury, Labour MP and former mayor of Poplar. This estate includes Chrisp Street Market, which was greatly commended by Lewis Mumford. The same era also saw the construction of the Robin Hood Gardens housing complex (overlooking the northern portal of the Blackwall Tunnel) - designed by architects Peter and Alison Smithson - and the similarly Modernist Balfron Tower, Carradale House and Glenkerry House (to the north) - designed by Ernő Goldfinger. Other notable buildings in Poplar include Poplar Baths, finally closed in 1988, which local campaigners hope to get redeveloped.
In 1998, following ballots of the residents, Tower Hamlets Council transferred parts of the Lansbury estate and six other Council housing estates within Poplar to Poplar HARCA, a new Registered Social Landlord set up for the purpose of regenerating the area. The following year, tenants on further estates voted to remain with the Council. However, after a lengthy consultation of all Council estates in Tower Hamlets begun in 2002, most estates in Poplar did transfer to Poplar HARCA, East End Homes and other landlords between 2005 and 2007.
Poplar also contains a Seamen's Mission, reflecting the area's long-standing connection to London's docks which for so many years gave the area employment. The original mission stood on Hale Street, but the current mission stands on the north side of East India Dock Road. Having fallen out of favour as a Mission, the building became the local headquarters of the Gas Board (testament to which is the gas fired streetlights to the rear of the property); it then became a Working men's club before it was finally converted into executive apartments.