The hospital was conceived in 1848 by a committee of Justices chaired by Sir John Wither Awdry for "providing an asylum for the pauper lunatics of the county of Wiltshire alone".

[1] Forty-eight acres of land was purchased from Mr T. H. S. Southeron at the end of Pans Lane in the parish of Roundway.

[1] The principal building material was stone from the Murhill quarries near Winsley, and the roof slates came from Wales.

[2] The hospital was called the Wiltshire County Lunatic Asylum when it received its first inmates on 19 September 1851.

In 1853 about 200 of the total of 333 patients were occupied on the hospital farm, in the kitchen, chopping wood or stonebreaking.

[1] By 1880 cricket, bowls, country walks, theatricals and "Christy Minstrels" style shows were available for the patients.

[2] 1930 also saw the Mental Treatment Act 1930, which affected the rights of patients and reinforced the idea that asylums were hospitals.

Some patients were transferred to the Old Manor Hospital in Salisbury and some to Old Park House, a large residential home in Devizes and a recent purchase by the Ministry of Health to provide better accommodation.

There was a trend to move mental care away from large institutions and this coincided with the development of modern effective antipsychotic drugs.

[1] By the 1960s the number of beds had been reduced to 800, and up to 300 patients were earning a small wage working in a rehabilitative factory managed by a local firm.