Historically part of the kingdom of Umhaill, it is famous as the home of the 16th century pirate queen Gráinne O'Malley.

The ruins of an O'Malley tower-house, known as Granuaile's Castle because of its most famous resident, are close to the pier at the eastern edge of the island.

In 1588, a ship from the Spanish Armada was wrecked on Clare Island and its men were killed by the O'Malleys.

On 29 September 1813 a fire, caused by careless disposal of the oil-lamp wicks, destroyed part of the tower and the lantern.

Clare Island Lighthouse has been refurbished and is now an upmarket guesthouse, while its optic is on permanent rotating display at the World of Glass museum and visitor centre in North West England.

[4] This is reputedly the only survey of its kind in Europe and is serving as a model for measuring the effects of climate change on environment.

[9] Clare Island is the setting for the Michael Morpurgo book The Ghost of Grania O'Malley.