The village at Rathdown did well from 1308 under the Normans:
the Le Brun and then the FitzGerald families.
In 1534, a castle,
20 houses,
a watermill
and a fresh water spring were recorded at Rathdown.
In the early 1990s, Dr. Leo Swan reported that photographs taken from the air showed signs that there was once a large village there.
In the Middle Ages there were about five hundred people living at Rathdown, and further south at Greystones was deserted.