Rathlin Castle, also known as Bruce's Castle, was a castle on Rathlin Island off the coast of County Antrim in Northern Ireland.
In 1306 after being defeated by Sir Aymer de Valence at the Battle of Methven and then by the Lord of Lorne at the Battle of Strathfillan, King Robert I of Scotland retired to Rathlin Castle for the winter with a small following of his most faithful men, including James Douglas, Lord of Douglas, Bruce's brothers Thomas, Alexander and Edward, as well as Sir Neil Campbell and Malcolm II, the Earl of Lennox. They were welcomed by the owners of the island and castle, the Scoto-Irish Bissett family, lords of the Glens of Antrim, who were later dispossessed of it by the English for this reason.
In July 1575, English forces led by Francis Drake and John Norreys attacked the castle with cannons and upon the surrender of the garrison of some MacDonnell's of Antrim, the defenders, except for some prisoners, and the island's residents were put to the sword resulting in the event known as the Rathlin Island Massacre. The main army of MacDonnells of Antrim led by Sorley Boy MacDonnell stationed at Ballycastle had witnessed the event taking place on Rathlin Island, where the families and valuables had been lodged for safety. Sorley Boy led his army in a successful retaliatory raid on Carrickfergus from where the Rathlin Island raid had left.
Scott, Robert the Bruce, pp 84–85. John, Barbours the Bruce, trans G. Eyre-Todd.