 The castle itself was built in the second quarter of the 13th century, as the seat of Duncan MacDougall, Lord of Lorn and grandson of Somerled. Duncan was unsuccessfully attacked by his Norwegian-backed brother, Uspak, who later died in an attack on Rothesay Castle with Norse forces in the 1230s. He had also travelled to Rome in 1237, and was the founder of nearby Ardchattan Priory. Duncan's son Ewen MacDougall inherited his father's title in the 1240s, and expanded the MacDougall influence, styling himself "King of the Isles". It is probable that Ewen built the three round towers onto the castle, and constructed and enlarged the hall inside.
