Grimmen was founded during theOstsiedlung, when about 1250 merchants and craftsman fromLower Saxony,Westphalia and the LowerRhine settled the site which then was part of thePrincipality of Rügen. The first document mentioning Grimmens is of 1267. In 1287, a report mentionsVogt Berthold taking office in the town, and further mentions that Grimmen had already been grantedLübeck law before. The actual charter is lost, thus the exact date when the town received Lübeck law remains uncertain. Accordingly, the 700th anniversary was celebrated in 1987. Since 1325, Grimmen belonged to theDuchy of Pomerania.
At the endSecond World War, Grimmen surrendered to theRed Army without fighting in April 1945. In the 1960s, numerous new factories and agricultural enterprises were set up, resulting in prosperity and physical growth of the city. AfterEast Germany's Communist regime collapsed followingDie Wende movement of 1989, the town's old buildings were reconstructed. After a reorganization of theKreis districts in 1994, Grimmen became capital of newly createdVorpommern-Rügen.
The first chapters ofDennis Wheatley's WWII spy thriller "They used dark forces" are set in 1944 Grimmen, where Wheatley's British agent Gregory Sallust arrives on a secret mission in Nazi Germany.