In 1758 the estate passed to James Murray of Broughton, who sold it in 1764 to the merchant and slave-trader Richard Oswald, who built the present Auchincruive House. Robert Adam provided a design for a house to James Murray in 1764, although Oswald built the house, in modified form, in 1767. Adam's scheme for the interiors was carried out as planned. Adam also designed Oswald's Temple, a castellated temple or tea-house, which stands on a nearby hill and was completed in 1778. Oswald was appointed as the British peace commissioner who negotiated the Treaty of Paris in 1783 when the American War of Independence came to an end. After the negotiations, he retired to Auchincruive where he died the following year.
