In the fourteenth and fifteenth centuries they owned vast tracts of land in counties Kildare, Meath, Wicklow and Carlow. By the early years of the twentieth century the Eustaces and their descendants had disposed of most of their property and land in Co. Kildare. The last surviving relic of the Eustace family in Ballymore Eustace is the effigy of a Eustace knight, now preserved in St. John's (Church of Ireland).
Rev. Sir Erasmus Borrowes built the present Victorian Castle around
the old Eustace tower house. Lt.Walter Borrowes Royal Navy was born at
Barretstown, and was killed serving on a submarine 23 January 1915. In
St. Johns Church Ballymore Eustace a plaque records that he died in the
“German War.”
The Borrowes continued to live at Barretstown Castle until
1919. Sir George Murray a Scotsman then purchased the castle and
estate. He converted the estate into a stud farm and planted many exotic
trees in the grounds of the castle. Elizabeth Arden, the perfume
manufacturer, bought the castle and estate in 1962. She commissioned the
architect Michael Scott to carry out improvements to the interior of
the castle. After Elizabeth Arden’s death in 1967, Galen Weston bought
the castle and estate; he carried out major works including the addition
of a beautiful lake in front of the castle.
The Weston family presented the castle and estate to the Irish Government in 1977, and for a period the government used the castle for meetings and conferences. Barretstown Castle and grounds are now a unique facility for sick children, set up in 1994 by the American film actor Paul Newman.