Mingulay (Miughalaigh) is the second largest of the Bishop's Isles in the Outer Hebrides of Scotland. Located south of Barra, it is known for its important seabird populations, including puffins, black-legged kittiwakes, and razorbills, which nest in the sea-cliffs, amongst the highest in the British Isles.
There are Iron Age remains, and the culture of the island was influenced by early Christianity and the Vikings. Between the 15th and 19th centuries Mingulay was part of the lands of Clan MacNeil of Barra, but subsequently suffered at the hands of absentee landlords.
After two thousand years or more of continuous habitation, the island was abandoned by its Gaelic-speaking residents in 1912 and has remained uninhabited since. It is no longer used for grazing sheep. The island is also associated with the "Mingulay Boat Song", although that was composed in 1938. The National Trust for Scotland has owned Mingulay since 2000.
In the Pleistocene era Mingulay was covered by the ice sheets which spread from Scotland out into the Atlantic Ocean beyond the Outer Hebrides. After the last retreat of the ice around 20,000 years ago, sea levels were lower than at present and circa 14,000 BP it was joined to a single large island comprising most of what is now the Outer Hebrides. Steadily rising sea levels since that time then isolated the island, which is made up of Hebridean gneiss interspersed with some granite. The ice deposited both erratic blocks of rock and boulder clay on the eastern side of the island around Mingulay Bay. The rest of the island is covered in peat, thin acidic soils, or bare rock.
Mingulay is part of the small archipelago known as the Bishop or Barra Isles which are "composed of a cluster of islands surrounded by a boisterous sea, making the passage of one island to another a matter of very considerable hazard" and which form the southern end of the larger Outer Hebrides group.
There is one large beach on the eastern side of the isle, where the only settlement of note ('The Village') was located, and a tiny cove at Skipsdale (Old Norse: ship valley).