The present Kinneil House has undergone various stages of development in its history. The land was granted to Walter Fitz Gilbert by Robert the Bruce in 1323, but whether or not he built a castle here is unknown, his main residence being Cadzow Castle.

What is known is that his great-great-great grandson James Hamilton, the 1st Lord Hamilton, built a large tower at Kinneil around 1470, standing atop a ravine through which the Gil Burn flows. It was extended around 1550 by his son, also James, 2nd Lord Hamilton, with further improvements taking place between 1553 and 1555, by which time it was known as the Palace of Kinneil.

In 1570 the tower was partly destroyed by James Douglas, the 4th Earl of Morton, and a replacement L-plan tower house was built slightly to the north east of the original tower. It had a vaulted half-basement, half-ground level storey, and one of the first floor rooms was also vaulted.

Between 1677 and 1688 Anne Douglas-Hamilton, the Duchess of Hamilton, along with her husband William Douglas, the 1st Earl of Selkirk (and later 3rd Duke of Hamilton), rebuilt and remodelled the original tower, building a huge five storey block on the original foundations – the 15th century gun loops can still be seen at the bottom of the back wall to the west.

They added four storey wings either side of the new central block, connecting the north wing to the L-plan tower. A planned range to the south-east – to mirror the L-shaped building – was never built. The Douglas-Hamilton’s also established parkland around the house, relocating the residents of the village of Kinneil to neighbouring Bo’ness. All that now remains of the village is one wall and the foundations of Kinneil Church.

Within a century Kinneil House was no longer occupied by the Hamiltons, who preferred instead Hamilton Palace, and it was rented out. The tenant in the second half of the18th century was Dr John Roebuck, who invited James Watt to stay on the estate and develop a steam engine to pump water out of his coal mines.

The house gradually fell into disrepair, and by 1936 the Hamiltons had sold it to Bo’ness Town Council, who intended to demolish it and build new houses on the site. A house-breaker was brought in to knock down the house and remove what features he wanted.

The 17th century block was completely gutted and the roof removed, but when work started on the demolition of the 16th century L-plan building and old plasterwork was revealed, some of the best preserved 16th and 17th century murals in Scotland came to light.

The demolition work was immediately stopped, and an ornate carved wooden ceiling rescued from a skip. Fragments of sixteenth century painted ceiling boards were recovered from a pile of wood to be burnt, but it was too late for other pieces.

With discoveries of such national importance, Kinneil House was taken into state care and is now in the guardianship of Historic Scotland. The main block has been re-roofed, as has the eastern portion of the L-plan tower housing the paintings. The house is only open on certain days during the year, but the outside can be viewed at any time.