There has been a windmill in Shirley since 1808 when William Alwen first built a post mill, worked by the Alwen family until October 1854, when it was destroyed by fire.

William Alwen’s grandson Richard built the present brick tower mill. The bricks may well have been made locally, and some of the machinery is thought to have come from a disused mill elsewhere.

However, the introduction of steam-powered roller mills, which were not only independent of the weather but produced the finer, whiter flour that customers preferred, made Shirley Windmill more and more uncompetitive, and eventually obsolete.

Despite growing competition, the Alwen family continued to operate Shirley Windmill until the late 1880s, when it was bought by Alfred Rayson. He was only able to use the mill for producing animal feed, until his death in 1892, when milling was abandoned.

The mill was struck by lightning in 1899 and again in 1906, when only the prompt action of the Croydon Fire Brigade saved it from destruction, though the sails and fantail were badly damaged.

By the 1920s, suburban expansion threatened the mill, but George Givan, a wealthy local resident, purchased the land and the mill in a bid to save it from demolition. In 1927 he began to restore the mill, including the replacement of the four sails and fantail. One of the restored sails was blown down in a gale in late 1935, and a more extensive restoration was carried out in 1935–6.

In 1951 the mill and the adjoining land were acquired by Croydon Corporation and a grammar school, John Ruskin School, was built. Demolition was considered but fortunately this threat was averted and the mill was incorporated within the school grounds. The Council maintained the mill and carried out more restoration work from time to time.

John Ruskin School was demolished in 1990, and some of the land was sold by Croydon Council to a property developer, which resulted in the construction of Postmill Close and the houses around the mill. This sale helped pay for restoration, and the long-held strategy to develop Shirley Windmill as a heritage site was secured in August 1996. A £218,000 grant was awarded by the Heritage Lottery Fund towards further extensive restoration and developing the site as a multi-media visitor attraction for both educational and leisure use. At long last Shirley Windmill is now available for everyone to visit, so that they can appreciate this interesting survival from Croydon’s past.