[1] All his property was declared forfeit, and his son and heir, William O'Shaughnessy, was forced into exile.
In 1697 Roger's estates were granted to Sir Thomas Prendergast, 1st Baronet, a Catholic neighbor; who had previously been a Jacobite and Confederate and had lost most of his own estates during the Cromwellian Wars; but this time decided to switch sides.
There followed decades of legal disputes with the Prendergasts, but the O'Shaughnessy family were never able to recover them.
[citation needed] Roger was the son of Dermot O'Shaughnessy.
Their children were:[1] Roger O'Shaughnessy succeeded to the O'Shaugnessy lands in Ireland in 1678.