Charles Sturt's son, also called Charles, inherited the property and sold it to Sir Charles Chad in 1817.
Chad invested significantly in the castle and Prince George visited in 1818, arriving to a salute from the castle guns.
The diplomat Sir Augustus Foster acquired the castle in 1840 on his retirement; he committed suicide at the castle 1848, having been in what his inquest termed a state of temporary insanity following a "disease of the heart and lungs".

A retired Indian Amy officer, Colonel William Waugh, bought the island in 1852, hoping to turn it into a profitable pottery works.
He carried out restoration work on the castle and built up a new Jacobethan-styled range around the south and east sides of the castle.
Waugh also constructed the crenelated gatehouse and clocktower at the entrance to the courtyard, and the Jacobethan-styled family pier by the sea below the castle.
The commercial venture was a failure and Waugh fled his creditors to Spain in 1857.

After a period of ownership by a Mr Faulkner, who continued the pottery scheme, the property was eventually resold in 1873 to the politician and lawyer George Cavendish-Bentinck for £30,000, who furnished the castle with an extensive collection of Italian Renaissance sculpture.
Cavendish-Bentinck closed the pottery works and gave the island as a family home to his son, William, paying for the castle to be extensively renovated; William and his wife Ruth moved into it in 1888.
Cavendish-Bentinck died in 1891 with extensive debts, forcing William to sell the castle and island to Major  Kenneth Robert Balfour.

The castle caught fire on 26 January 1896 and the interiors were gutted by the blaze.
Balfour rebuilt the property with the services of the architect Philip Brown, softening the more complex aspects of the castle's design.
Balfour's wife, Margaret Anne, fell ill and he decided to sell the island in 1901 to the stockbroker Charles van Raalte.

Van Raalte maintained a lavish lifestyle at the castle, which by now had 38 bedrooms, holding grand house-parties during the summer months, complete with servants and a part-time musical band and assembling a rare collection of around 250 historical musical instruments from Europe, Asia and Africa at the castle.
Charles died in 1908 but his wife Florence stayed until 1925.
On Florence's death in 1927 the castle was sold to Sir Arthur Wheeler, who promptly decided to auction off the remaining contents with the intent of demolishing the property.
The sale, which included some of Van Raalte's collection of instruments, paintings and a 5,000 book library, produced £22,300.

The castle was not demolished as planned and instead was purchased by Mary Bonham-Christie for £125,000 later that year.
She decided to live in a nearby house rather than the castle itself, allowing the island to return to nature and the castle to fall into disrepair.
By the time of Bonham-Christie's death in 1961 the roof had partially collapsed and a tree was growing up through the centre of the building.
Facing large death duties, Bonham-Christie's grandson put the island up for sale, before agreeing to donate it to the state in lieu of taxes.

The National Trust took on ownership of the castle and island in 1962 but considered the castle to be of "little antiquity or architectural interest".
The John Lewis Partnership leased the castle from the Trust for use as a corporate hotel by their employees, gradually restoring the buildings in stages and they remain the current tenants.
Some of the 19th century interior features still survive, including wood panelling and ornamental ceilings, with some carved stone fireplaces from Venice; the castle also has four cannons, probably dating from the 17th or early 18th century.
The castle is protected under UK law as a Grade II listed building.
Charles Sturt's son, also called Charles, inherited the property and sold it to Sir Charles Chad in 1817. Chad invested significantly in the castle and Prince George visited in 1818, arriving to a salute from the castle guns. The diplomat Sir Augustus Foster acquired the castle in 1840 on his retirement; he committed suicide at the castle 1848, having been in what his inquest termed a state of temporary insanity following a "disease of the heart and lungs".
A retired Indian Amy officer, Colonel William Waugh, bought the island in 1852, hoping to turn it into a profitable pottery works. He carried out restoration work on the castle and built up a new Jacobethan-styled range around the south and east sides of the castle. Waugh also constructed the crenelated gatehouse and clocktower at the entrance to the courtyard, and the Jacobethan-styled family pier by the sea below the castle. The commercial venture was a failure and Waugh fled his creditors to Spain in 1857.
After a period of ownership by a Mr Faulkner, who continued the pottery scheme, the property was eventually resold in 1873 to the politician and lawyer George Cavendish-Bentinck for £30,000, who furnished the castle with an extensive collection of Italian Renaissance sculpture. Cavendish-Bentinck closed the pottery works and gave the island as a family home to his son, William, paying for the castle to be extensively renovated; William and his wife Ruth moved into it in 1888. Cavendish-Bentinck died in 1891 with extensive debts, forcing William to sell the castle and island to Major  Kenneth Robert Balfour.
The castle caught fire on 26 January 1896 and the interiors were gutted by the blaze. Balfour rebuilt the property with the services of the architect Philip Brown, softening the more complex aspects of the castle's design. Balfour's wife, Margaret Anne, fell ill and he decided to sell the island in 1901 to the stockbroker Charles van Raalte.
Van Raalte maintained a lavish lifestyle at the castle, which by now had 38 bedrooms, holding grand house-parties during the summer months, complete with servants and a part-time musical band and assembling a rare collection of around 250 historical musical instruments from Europe, Asia and Africa at the castle. Charles died in 1908 but his wife Florence stayed until 1925. On Florence's death in 1927 the castle was sold to Sir Arthur Wheeler, who promptly decided to auction off the remaining contents with the intent of demolishing the property. The sale, which included some of Van Raalte's collection of instruments, paintings and a 5,000 book library, produced £22,300.
The castle was not demolished as planned and instead was purchased by Mary Bonham-Christie for £125,000 later that year. She decided to live in a nearby house rather than the castle itself, allowing the island to return to nature and the castle to fall into disrepair. By the time of Bonham-Christie's death in 1961 the roof had partially collapsed and a tree was growing up through the centre of the building. Facing large death duties, Bonham-Christie's grandson put the island up for sale, before agreeing to donate it to the state in lieu of taxes.
The National Trust took on ownership of the castle and island in 1962 but considered the castle to be of "little antiquity or architectural interest". The John Lewis Partnership leased the castle from the Trust for use as a corporate hotel by their employees, gradually restoring the buildings in stages and they remain the current tenants. Some of the 19th century interior features still survive, including wood panelling and ornamental ceilings, with some carved stone fireplaces from Venice; the castle also has four cannons, probably dating from the 17th or early 18th century. The castle is protected under UK law as a Grade II listed building.
Brownsea Castle