In the 17th and 18th centuries, Denmark imposed harsh trade restrictions on Iceland. Natural disasters, including volcanic eruption and disease, contributed to a decreasing population. Pirates from several countries, including the Barbary Coast, raided Iceland's coastal settlements and abducted people into slavery. A great smallpox epidemic in the 18th century killed around a third of the population. In 1783 the Laki volcano erupted, with devastating effects. In the years following the eruption, known as the Mist Hardships (Icelandic: Móðuharðindin), over half of all livestock in the country died. Around a quarter of the population starved to death in the ensuing famine.