Complex sentence: It reached the Faroe Islands on a norwegian ship "Kongen af Preussen," which wrecked on the Scotish island Lewis, the wreck drifted to Hvalba in Suðuroy in may 1768, already in 1769 had the rat established itself in Tórshavn.
Split into simpler sentences: It reached the Faroe Islands on the Norwegian ship "Kongen af Preussen," which wrecked on the Scotish island Lewis. The wreck drifted to Hvalba in Suðuroy in May 1768; in 1769, the rat had already established itself in Tórshavn.