The land that Whitehaven Castle sits upon has been occupied since the thirteenth century, it is said to have Druidic associations. It is believed that there was once a stone circle with the name of Corpse-Circle, meaning Dead-Ring on this site.
The land was given to the priory of St. Bees in 1250 by Gilbert of Hothwaite. 'Hothwaite' was the land between the new road out of Whitehaven and Midgey Ghyll. Situated on this land was the Flatt mansion. Eventually this land fell into the hands of Sir George Fletcher.
Sir John Lowther purchased the Flatt in 1675 from Sir George Fletcher and made many improvements. In 1686 the castle was described by Mr Denton as, "a stately new pile of building, lately erected by ye said Sir John Lowther".
In 1769, Sir James Lowther, who was later to be made The Earl of Lonsdale, had the Flatt rebuilt following a fire.
More than 200 years after the Lowthers had initially purchased the castle, the large wall around the castle and grounds was removed, finally opening up the park to the people of Whitehaven. In 1923 the park was officially opened, along with the unveiling of the Cenotaph. The Cenotaph was designed by a local artist and is graced by the figure of 'Peace'. A roll of honour containing the names of the fallen plus a local newspaper were encased in a lead casket and buried in the foundations.
In 1924 the Earl of Lonsdale sold the castle to Mr H. Walker. The castle was donated to the town, along with monies to carry out necessary repairs and alterations. The castle was duly modified and it replaced the old infirmary which had been difficult to bring up-to-date.
In 1951, due to inadequacies at the infirmary, an architect was appointed who duly came up with the plans for the West Cumberland Hospital. The new West Cumberland Hospital was the first hospital built in England following the creation of the National Health Service. It was officially opened on October 21, 1964 by Queen Elizabeth, the Queen Mother.
The castle infirmary and the new hospital coexisted until 1986, when due to fire regulations, the infirmary had to close to its patients. In the event of a fire the elderly patients would have to have been evacuated over the rooftop, not a satisfactory solution. Today, following extensive renovation, the castle in Whitehaven has been converted into private accommodation.