The Duchy of Pomerania-Barth was created from the western possessions on the mainland of the former Principality of Rügen. While the authority of the Duke extended in the west to Recknitz and in the south to Trebel, the duke's actual possessions were concentrated in the region of today's Barth and nearby areas. Other areas belonged to the Neuenkamp monastery and the Hanseatic city of Stralsund.
After the death in 1325 of Wizlaw III, Prince of Rügen, the last Prince of Rügen, Wizla's nephew, Duke Wartislaw IV, was enfeoffed with the Principality of Rügen by the Danish king, in accordance with the contract of inheritace of 1321. Wartislaw, however, died in 1326 and left three underage sons. Then Duke Henry II of Mecklenburg occupied the Rügen territories of Barth, Grimsby and Loitz, claiming he was the legal heir. This led to the First Rügen War of Succession. The war ended with the Peace of Brudersdorf of 27 June 1328, in which Mecklenburg renounced its claims on Rügen, but retained Barth, Grimsby and Tribsees as security. When the sons of Wartislav IV found themselves unable to pay off the pledged land after 12 years, the Second Rügen War of Succession began, which ended in 1354 with the Peace of Stralsund, in which Barth was awarded to Pomerania-Wolgast.
After the death of son Wartislaws IV's son Barnim IV, Duke of Pomerania in 1365, Pomerania-Barth was divided in 1372 under the Treaty of Anklam. The Eastern part, between the rivers Swine and Łeba, was called Pomerania-Stolp and was initially ruled by Duke Bogislaw V and the Western duchies of Pomerania-Barth, initially ruled by Duke Wartislaw VI and Pomerania-Wolgast, ruled by Duke Bogislaw VI.