James White, proprietor of the Shawfield Chemical Works on the Glasgow-Rutherglen Road, bought the lands of Meikle Overtoun from Gabriel Lang of Greenock in 1859. He commissioned the architect James Smith to design a Scots Baronial mansion, after the fashion of Queen Victoria's Balmoral. These mansions and castles were part of a Gothic revival in architecture, drawing on medieval and Renaissance styles, in reaction to the revivalist Neo-classical architecture of the early half of the 19th century.

Smith's daughter Madeleine had just been released from prison after her trial for poisoning her lover Emile L'Angelier with the case not proven. Smith was very shaken by the scandal and died, a young man, in 1863.

The gardens were laid out by Edward Kemp, a foremost landscape designer of the day.

The family money came from White's Chemical Works. These had been opened in the early 19th century and only ceased functioning in 1968. The main product was chrome, but the working conditions were abhorrent, and the ground lies unusable to this day.

James White died in 1884 and his only son John Campbell White took over.

Keir Hardie, the founder of the Labour Party, attacked the Whites for the conditions of slavery they maintained for their workers, while acting philanthropically, particularly in the Dumbarton area where they donated land for the municipal buildings, supported local churches and voluntary organisations. Lord Overtoun, as John Campbell White had become, could only claim that he had never been to his works for such a long time that he was unaware of the conditions he was forcing his workers to suffer.

The original east entrance from Milton was deemed too steep for carriages and in 1895 a new west entrance and lodge were opened, at the foot of Garshake Road, now a foot access to the house.

When Lord Overtoun died in 1908 the estate passed to his sister Fanny's son, John Douglas Campbell White (1871-1940), who was an occasional resident. Just before he died, in 1939, he made the house and grounds over to Dumbarton Burgh Council.

During World War II the house was used as a convalescent home for both locals and injured army personnel, and the remains of an army camp are on the right at the top of the Milton entrance.

After the War the house was converted into a maternity hospital, opening in April 1948 with 25 beds in nine wards. Many mothers remember seeing the sight of angels painted in the frescoes on the ceilings, believing themselves for a minute in heaven. It and Braeholm in Helensburgh served the maternity needs of the district until the Vale of Leven Hospital maternity unit opened in September 1970 with 80 beds.

In 1975 the house was reopened for the Quality of Life Experiment, Dumbarton District having been chosen as the Scottish area to receive funding to bring in culture of all sorts to help improve people's quality of life.

In 1976 the house passed to the Spire Christian Fellowship with the aims of spiritual education, leisure activities and cultural projects. In 1980 the nature trail was opened, and throughout the 80s Youth With a Mission occupied the house. It served as Craiglockart Hospital, Edinburgh, for the World War I film Regeneration, released in 1997.

In 2000 Scot nursing and Pastor Bob Hill's Christian Centre for Hope and Healing put in bids for the house, and the more secure financial backing of the latter won, offering youth activities, supported accommodation for women, bed and breakfast, nature trails and open access to the house.