In the 18th century, Walmer Castle became the official residence of the Lord Warden of the Cinque Ports.
The Lord Warden was originally a medieval title linked to five key ports along the coast of England; the position's prominence had faded, but it still retained important judicial and military functions.
When Lionel Sackville, the Duke of Dorset, was appointed to the post in 1708 he decided that the existing residence in Dover Castle was unsatisfactory, probably because of the semi-ruinous state of the castle, and moved into Walmer Castle instead.

The Duke occupied the post of Lord Warden until 1765, save for two periods when it was filled by James Butler, the Duke of Ormonde and John Sidney, the Earl of Leicester.
He carried out extensive work to make the castle more habitable, building extensions towards the north bastion and constructing a small house in the south bastion for the soldiers.
Under the subsequent Lord Wardens, the politicians Robert Darcy, the Earl of Holderness, and Francis North, the Earl of Guildford, the castle continued to house artillery but it became increasingly less military in character.

The Prime Minister William Pitt the Younger was then made the Lord Warden in 1792.
Pitt was badly in debt and King George III believed that the post, which came with a salary of £3,000 a year, would usefully supplement Pitt's income.
Pitt made extensive use of the castle and by 1803 he used it as his main residence in an effort to reduce his living costs.
Pitt's niece, Lady Hester Stanhope, joined him at Walmer between 1803 and 1806; together with Pitt, she carried out extensive work on the castle gardens, transforming them from a simple kitchen garden into a set of landscaped ornamental enclosures; Stanhope enlisted the Dover militia to help with the landscaping and planting.

With the outbreak of the French Revolutionary Wars, Pitt became energetically involved in the protection of the ports along the coast, entertaining the local garrison commanders, naval captains and the local gentry at Walmer on a regular basis.
After Pitt resigned as Prime Minister in 1801, fears remained of a French invasion and he formed a volunteer cavalry unit at Walmer Castle, where he lived with his new officers.
 He also formed a unit of bombardier infantry and a fleet of 35 fishing boats called luggers, which he armed with 12-pound (5.4 kg) or 18-pound (8.2 kg) guns, reviewing them from the castle.
Stanhope remarked on the constant drilling of army units around the castle during her time there.

Robert Jenkinson, the Earl of Liverpool, took possession of Walmer Castle following the death of Pitt in 1806.
Liverpool was a favourite of King George's, and his appointment as Lord Warden was again intended to provide a valuable income and a country retreat.
As Prime Minister, Liverpool used Walmer as a personal retreat and as a location for private political discussions with selected guests.
In the 18th century, Walmer Castle became the official residence of the Lord Warden of the Cinque Ports. The Lord Warden was originally a medieval title linked to five key ports along the coast of England; the position's prominence had faded, but it still retained important judicial and military functions. When Lionel Sackville, the Duke of Dorset, was appointed to the post in 1708 he decided that the existing residence in Dover Castle was unsatisfactory, probably because of the semi-ruinous state of the castle, and moved into Walmer Castle instead.
The Duke occupied the post of Lord Warden until 1765, save for two periods when it was filled by James Butler, the Duke of Ormonde and John Sidney, the Earl of Leicester. He carried out extensive work to make the castle more habitable, building extensions towards the north bastion and constructing a small house in the south bastion for the soldiers. Under the subsequent Lord Wardens, the politicians Robert Darcy, the Earl of Holderness, and Francis North, the Earl of Guildford, the castle continued to house artillery but it became increasingly less military in character.
The Prime Minister William Pitt the Younger was then made the Lord Warden in 1792. Pitt was badly in debt and King George III believed that the post, which came with a salary of £3,000 a year, would usefully supplement Pitt's income. Pitt made extensive use of the castle and by 1803 he used it as his main residence in an effort to reduce his living costs. Pitt's niece, Lady Hester Stanhope, joined him at Walmer between 1803 and 1806; together with Pitt, she carried out extensive work on the castle gardens, transforming them from a simple kitchen garden into a set of landscaped ornamental enclosures; Stanhope enlisted the Dover militia to help with the landscaping and planting.
With the outbreak of the French Revolutionary Wars, Pitt became energetically involved in the protection of the ports along the coast, entertaining the local garrison commanders, naval captains and the local gentry at Walmer on a regular basis. After Pitt resigned as Prime Minister in 1801, fears remained of a French invasion and he formed a volunteer cavalry unit at Walmer Castle, where he lived with his new officers.  He also formed a unit of bombardier infantry and a fleet of 35 fishing boats called luggers, which he armed with 12-pound (5.4 kg) or 18-pound (8.2 kg) guns, reviewing them from the castle. Stanhope remarked on the constant drilling of army units around the castle during her time there.
Robert Jenkinson, the Earl of Liverpool, took possession of Walmer Castle following the death of Pitt in 1806. Liverpool was a favourite of King George's, and his appointment as Lord Warden was again intended to provide a valuable income and a country retreat. As Prime Minister, Liverpool used Walmer as a personal retreat and as a location for private political discussions with selected guests.
Walmer Castle