For about 400 years centered around 1200 AD, Viking farmers lived in two colonies in Greenland, growing a few crops and raising herds of cattle and sheep. As many as 2500 Vikings may have inhabited the two colonies before they disappeared.
Conventional wisdom says that they died out as the climate got colder after the end of the Medieval Warm Period, capped by a huge eruption in Indonesia on Lombok Island in 1257 AD that is ranked the most powerful in the last 7000 years by geologists, according to a recent article in Smithsonian magazine. Large volcanic eruptions are known to cause significant cooling of climate over several years due to reflection of sunlight back to space from small sulfuric acid drops lofted high into the atmosphere during the eruption. You can read more about this fascinating history at https://www.smithsonianmag.com/history/why-greenland-vikings-vanished-180962119/.
