This summary is based on background to the 'Streatfeild Manuscripts' held by the Kent History and Library Centre, Maidstone, on the National Archives web site, reference U908.
Tthe original with more information is HERE.
The Streatfeilds were yeomen, who by the end of the sixteenth century had interests in the Wealden iron industry. Richard Streatfeild was leasing Canserns Forge in Hartfield, Sussex, in 1589 and Pilbeams Forge in Chiddingstone and Withyham on the borders of Kent and Sussex in 1592 and he died in possession of the latter in 1601. In his will he was still termed a yeoman though by this time he had become a lord of a manor, the manor of Cowden Leighton having been purchased in 1591 by himself and his father from a neighbouring noble family in decline, the Burgh family of Starborough Castle in Lingfield, Surrey. Further lands of the Burgh family were purchased in the same year and in 1596 the manors of Chiddingstone Cobham and Tyehurst were mortgaged by Thomas, Lord Burgh, to Richard Streatfeild's trustees. The mortgage was never repaid and the manors remained in the possession of members of the Streatfeild family. Details of these transactions are recorded in "The History and Topographical Survey of the County of Kent" by Edward Hasted, 1797, vol 3 'Parishes: Chiddingstone'. The text is on British History Online and a searcheable copy is on The Weald website.
After the beginning of the seventeenth century members of the main branch of the family were referred to as gentlemen and continued to acquire property steadily, though at the same time either by deliberate policy or as a result of intestacy the younger children of each generation were well provided with parts of the estate.
Important additions to the estate were made by bulk purchases of property particularly by the acquisition in 1689 of the property of the Jemett family in Edenbridge and Cowden and in 1699 of the property of the old established family of Seyliard in Brasted, Edenbridge, Chiddingstone and Cowden. Also during the late seventeenth century the dwelling house of the family in Chiddingstone, High Street House, was rebuilt and a picture of the red-brick house surrounded by formal gardens is portrayed on a map of 1702. It presumably replaced a timber-framed house similar to those remaining in the village today and was in turn succeeded in the mid-nineteenth century by a mock-gothic castle, the style of the family's dwelling matching their rising status and wealth. As all the adjoining property to the house was gradually acquired during the eighteenth century the grounds were extended and ultimately about half the village disappeared into the Park and the road through the village was diverted away from the house and round the Park.
As well as being considerable landowners both Henry Streatfeild (d.1709) and his son. Henry (d.1747) were lawyers with chambers in Lincoln's Inn. Henry (d.1747) was one of the Deputy Lieutenants for the county but managed to avoid what he described as "that trouble-some office" of sheriff of the county, on the grounds that he held the office of one of the Gentlemen of the Privy Chamber. He also held the more prosaic office of surveyor of highways for Chiddingstone parish, a duty which local landowners usually left to one of the villagers. In addition he was one of the churchwardens of Chiddingstone. It was not until 1792 that a member of the family became sheriff, this being Henry Streatfeild (d.1829).
An important event in the rise of the family's fortunes was the marriage of Henry Streatfeild (d.1762) and Ann Sidney, heiress of Jocelin, 7th Earl of Leicester, who brought with her a marriage portion of £10,000 and estates in Glamorganshire. Further purchases increasing the size of the estate in Kent were made throughout the late eighteenth century by Ann Streatfeild as a widow during her son's minority and then by her son, Henry himself.
Another large addition to the estate came in 1801 when Henry Streatfeild inherited from a distant cousin, Thomas Streatfeild of Oxted, in Surrey property in Oxted and on the borders of Kent and Surrey in Lingfield, Limpsfield, Edenbridge and Cowden, as well as a colliery near Manchester. Part of the Welsh estate was sold in 1809, due to the difficulties of administering it at a distance and the poor monetary return provided by it, and the money from the sale was divided among the younger children of Ann Streatfeild.
In 1836 and 1837, High Street House was rebuilt, as already mentioned, in the Gothic style and gradually became known as Chiddingstone Castle. The architect was H.E. Kendall and the builder "Mr. Cubitt" .