Threave Castle is first recorded in 1400 when Archibald "The Grim", third Earl of Douglas, died there on Christmas Eve. Archibald's nickname was given to him by the English - he ejected them from Lochmaben Castle and that corner of Scotland in 1384. It is likely that the present castle was built for Archibald after he became Lord of Galloway in 1369. The son of Archibald "The Grim" married Margaret Stewart, the eldest daughter of King Robert III and Margaret lived in Threave for more than 25 years after her husband had died in battle. In the middle of the 15th century, King James II began to destroy the power of the Douglases, starting with the murder of the Earl of Douglas at Stirling Castle in 1452. By 1455 all the Douglas castles had been destroyed and only Threave remained. Siege guns were used but the artillery fortification round the tower house allowed it to withstand the cannon. It seems that it eventually surrendered after two months because the defenders were bribed with money and land. In the 16th century the Maxwells became hereditary custodians of Threave (though their main seat was at Caerlaverock Castle). In the 17th century the Maxwells supported King Charles I and Threave Castle was besieged by the Covenanters. After holding out for thirteen weeks, King Charles himself authorised Robert Maxwell to walk out of the castle with honour.

see "Threave Castle" on Glenn Gibson's website