Iceland is a small, sparsely-populated island in the North Atlantic Ocean. It was uninhabited prior to AD 874, when Vikings began to colonize it. One of the oldest republics in the world, it was in the Norwegian, and later Danish, spheres of influence before acquiring complete autonomy during World War II. It is one of very few nations in the world without armed forces. The capital and largest city is Reykjavik.
A geologically young land, Iceland is located on both the Iceland hotspot and the Mid-Atlantic Ridge, which runs right through it. This location means that the island is highly geologically active with many volcanoes, notably Hekla, Eldgjá, Herðubreið, and Eldfell. The volcanic eruption of Laki in 1783–1784 caused a famine that killed nearly a quarter of the island's population. In addition, the eruption caused dust clouds and haze to appear over most of Europe and parts of Asia and Africa for several months afterward, and affected climates in other areas.