In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Calshot like this:
CALSHOT-CASTLE, an extra-parochial tract in New Forest district, Hants; at the W side of the mouth of Southampton water, 7 miles SSE of Southampton. Pop., 23. Houses, 6. A castle here was one of the numerous small forts built by Henry VIII., for protecting the south coast; and is now a dwelling house.A lighthouse is here, with a fixed light, bright and red; and a light-vessel, called the Calshot Spit light, is in the neighbourhood; with a minute revolving light. Calshot-Castle is also a coastguard station.
A Vision of Britain through Time includes a large library of local statistics for administrative units. For the best overall sense of how the area containing Calshot has changed, please see our redistricted information for the modern district of New Forest. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Calshot and units named after it.
GB Historical GIS / University of Portsmouth, History of Calshot, in New Forest and Hampshire | Map and description, A Vision of Britain through Time.
Date accessed: 24th July 2016
Click here for more detailed advice on finding places within A Vision of Britain through Time, and maybe some references to other places called "Calshot".