Montserrat ( MONT-sə-RAT) is a British Overseas Territory in the Caribbean. The island is in the Leeward Islands, which is part of the chain known as the Lesser Antilles, in the West Indies. Montserrat measures approximately 16 km (10 mi) in length and 11 km (7 mi) in width, with approximately 40 km (25 mi) of coastline. Montserrat is nicknamed "The Emerald Isle of the Caribbean" both for its resemblance to coastal Ireland and for the Irish ancestry of many of its inhabitants. Montserrat is the only non-fully sovereign full member of the Caribbean Community and the Organisation of Eastern Caribbean States.

On 18 July 1995, the previously dormant Soufrière Hills volcano, in the southern part of the island, became active. Eruptions destroyed Montserrat's Georgian era capital city of Plymouth. Between 1995 and 2000, two-thirds of the island's population was forced to flee, primarily to the United Kingdom, leaving fewer than 1200 people on the island in 1997 (rising to nearly 5000 by 2016). The volcanic activity continues, mostly affecting the vicinity of Plymouth, including its docking facilities, and the eastern side of the island around the former W. H. Bramble Airport, the remnants of which were buried by flows from volcanic activity on 11 February 2010.

An exclusion zone, encompassing the southern half of the island to as far north as parts of the Belham Valley, was imposed because of the size of the existing volcanic dome and the resulting potential for pyroclastic activity. Visitors are generally not permitted entry into the exclusion zone, but a view of the destruction of Plymouth can be seen from the top of Garibaldi Hill in Isles Bay. Relatively quiet since early 2010, the volcano continues to be closely monitored by the Montserrat Volcano Observatory.A new town and port are being developed at Little Bay, which is on the northwest coast of the island. While this construction proceeds, the centre of government and businesses is at Brades.