The park, with artificial lakes, was formerly part of the estate of a large stately home Wanstead House (1722–1825), built by Richard Child, 1st Earl Tylney.

The English Place-Names Society derives the name from the Anglo-Saxon words waenn, meaning a hill or mound, and stede, a place or settlement.

In 1717 the Royal Society lent Pound Huygens's 123-foot focal length object-glass, which he set up in Wanstead Park.

Pound's observations with it of the five known satellites of Saturn enabled Halley to correct calculations of their movements; and Newton employed, in the third edition of the Principia, his micrometrical measures of Jupiter's disc, of Saturn's disc and ring, and of the elongations of their satellites; and obtained from him data for correcting the places of the comet of 1680.

Pound trained his sister's son, James Bradley, and many of their observations were made together, including the opposition of Mars in 1719, and the transit of Mercury on 29 October 1723.

Their measurement of γ Virginis in 1718 was the first made of the components of a double star and was directed towards the determination of stellar parallax.

However the most likely explanation is that it was placed there by the landlord of 1752, David Jersey (corrupted by centuries of repainting and re-cutting the inscription to D Jerry on the plaque), commemorating a feast which included a huge cherry pie.

The Royal Commercial Travellers Schools were sited in Wanstead from their foundation in 1845 by John Robert Cuffley until their move to Pinner in 1855.

The schools at Wanstead provided housing, food, clothing and education for up to 130 children of commercial travellers who had died or became unable to earn their livelihood.

[7] The Royal Merchant Navy School was founded in St George in the East, London in 1827 before moving to Hermon Hill, Wanstead in 1862.

[citation needed] Wanstead Flats was used for Anti-Aircraft batteries protecting London, Barracks for Pre-D-Day troops and a Prisoner-of-War Camp subsequently.