Short answers, pulled from the story.
The island known today as Saaremaa appeared in early medieval Scandinavian texts under the name Eysýsla. Old Norse speakers used this term to mean 'the island district' when distinguishing it from Aðalsýsla, or the great mainland district.
The Livonian Brothers of the Sword conquered Saaremaa in 1227 during the Livonian Crusade. Local resistance remained strong even after the initial military defeat before a treaty signed by the Osilians and the Master of the Order ended the conflict following the Battle of Saule in 1236.
Soviet military authorities declared Saaremaa a restricted zone closed to all non-local civilians in 1946. This status remained in effect until 1989 when restrictions finally lifted, isolating the population for over four decades.
Kaali crater sits on the island as one of its most famous geological features with the largest of nine unique meteorite craters measuring approximately 45 meters in diameter. It contains a small lake known as Lake Kaali and has an age estimate varying between 4000 ± 1000 BCE and 660 ± 85 BCE.
Saaremaa hosts 80% of all plant species found in Estonia across its diverse terrain including about 120 local plant species that have received special protection status due to their rarity. Altogether 1200 species of vascular plants grow here including rare flowers like Rhinanthus osiliensis.