Eilean Mhuire is the most easterly of the Shiant Islands in the Outer Hebrides

Outer Hebrides

The Outer Hebrides also known as the Western Isles and the Long Island, is an island chain off the west coast of Scotland. The islands are geographically contiguous with Comhairle nan Eilean Siar, one of the 32 unitary council areas of Scotland...

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Once populated Eilean Mhuire is now used only for grazing sheep. There are various ruins on the island and the Ordnance Survey

Ordnance Survey

Ordnance Survey , an executive agency and non-ministerial government department of the Government of the United Kingdom, is the national mapping agency for Great Britain, producing maps of Great Britain , and one of the world's largest producers of maps.The name reflects its creation together with...

 mark the remains of "St. Mary's Chapel" on the western side of the island, having been informed in 1851 that the island was a priest's refuge "in the time of Knox

John Knox

John Knox was a Scottish clergyman and a leader of the Protestant Reformation who brought reformation to the church in Scotland. He was educated at the University of St Andrews or possibly the University of Glasgow and was ordained to the Catholic priesthood in 1536...

". There is certainly a local tradition of the existence of such a building, although Nicolson (2002) believes this to be mistaken and speculates that Eilean Mhuire may have been a pre-Norse hermitage

Hermitage (religious retreat)

Although today's meaning is usually a place where a hermit lives in seclusion from the world, hermitage was more commonly used to mean a settlement where a person or a group of people lived religiously, in seclusion.-Western Christian Tradition:...

. (There was however a chapel devoted to the Virgin Mary on nearby Eilean an Taighe

Eilean an Taighe

Please note "Eilean an Taighe", or "Eilean Taigh" is a fairly common island nameEilean an Tighe or Eilean an Tigh, meaning "home island", is one of the Shiant Isles...

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Writing in 1549, Donald Monro

Donald Monro (Dean)

Donald Monro was a Scottish clergyman, who wrote an early and historically valuable description of the Hebrides and other Scottish islands and enjoyed the honorific title of “Dean of the Isles”.-Origins:...

, Dean of the Isles stated of Eilean Mhuire that it was:

callit Senchastle by the Eriche, that is the alde castle ile in the Englishe, an strenthe, full of corne and grassinge, full of wyld fowls nests, and verey guid for fishing. It perteins to M’Cloyd of the Lewis.

Today, Seann Chaisteal (old castle) is the name of the flat-topped tidal islet at the south eastern extremity of Eilean Mhuire. This is a "large tidal rock on which there never was a building of any kind", and the name may come from the rock's appearance.