Rathmacknee Castle is a tower house and National Monument located in County Wexford, Ireland.

[2][3][4] Rathmacknee Castle is located in southeast County Wexford, 6.3 km (3.9 mi) west of Rosslare.

[5] Rathmacknee Castle is believed to have been built by John Rosseter (Rossiter, Rositer, Rosceter) who was made seneschal of the Liberty of Wexford c. 1415.

The Rossiters remained Catholic after the Reformation but stayed loyal to the monarchy and continued to hold their lands.

Col. Thomas Rosseter fought against Oliver Cromwell at Wexford in the Irish Confederate Wars and the castle and lands were confiscated in 1654.