Universitäts- und Hansestadt Greifswald, Germany

The salt trade helped Eldena Abbey to become an influential religious center, and Greifswald became a widely known market. When the Danes had to surrender their Pomeranian lands south of the Ryck, after losing the Battle of Bornhöved in 1227, the town succeeded to the Pomeranian dukes. In 1241, the Rugian prince Wizlaw I and the Pomeranian duke Wartislaw III both granted Greifswald market rights. In 1250, the latter granted the town a charter under Lübeck law, after he had been permitted to acquire the town site as a fief from Eldena Abbey in 1248.

When Jazco of Salzwedel from Gützkow founded a Franciscan friary within the walls of Greifswald, the Cistercians at Eldena lost much of their influence on the city's further development. Just beyond Greifswald's western limits, a town-like suburb (Neustadt) arose, separated from Greifswald by a ditch. In 1264, Neustadt was incorporated and the ditch was filled in.

Eldena Abbey and the major buildings of Greifswald were erected in the North German Brick Gothic (Backsteingotik) style, found along the entire southern coast of the Baltic.

Due to a steady population increase, Greifswald became at the end of the 13th century one of the earliest members of the Hanseatic League, which further increased its trade and wealth. After 1296, Greifswald's citizens no longer needed to serve in the Pomeranian army, and Pomeranian dukes did not reside in the city.

In 1456, Greifswald's mayor Heinrich Rubenow laid the foundations of one of the oldest universities in the world, the University of Greifswald, which was one of the first in Germany, and was, successively, the single oldest in Sweden and Prussia.

In the course of Reformation, Eldena Abbey ceased to function as a monastery. Its possessions fell to the Pomeranian dukes; the bricks of its Gothic buildings were used by the locals for other construction. Eldena lost its separate status and was later absorbed into the town of Greifswald. The religious houses within the town walls, the priories of the Blackfriars (Dominicans) in the northwest and the Greyfriars (Franciscans) in the southeast, were secularized. The buildings of the Dominicans (the "black monastery") were turned over to the university; the site is still used as part of the medical campus. The Franciscan friary ("the "grey monastery") and its succeeding buildings are now the Pomeranian State Museum.

During the Thirty Years' War, Greifswald was occupied by (Catholic) Imperial forces from 1627 to 1631, and thereafter, under the Treaty of Stettin (1630), by (Protestant) Swedish forces.

During the Thirty Years' War, Swedish forces entered the Duchy of Pomerania in 1630. Greifswald was besieged by Swedish troops on 12 June 1631 and surrendered on 16 June. Gustavus Adolphus of Sweden had returned from Brandenburg to supervise the siege, and upon his arrival received the university's homage for the liberation from Catholic forces. After the Thirty Years' War (1618–1648), Greifswald and the region surrounding it became part of the Kingdom of Sweden. Swedish Pomerania, as it was then called, remained part of the Swedish kingdom until 1815, when it became part of the Kingdom of Prussia as the Province of Pomerania. In 1871, it devolved to Germany.

The Thirty Years' War had caused starvation throughout Germany, and by 1630 Greifswald's population had shrunk by two-thirds. Many buildings were left vacant and fell into decay. Soon, other wars followed: the Swedish-Polish War and the Swedish-Brandenburg War both involved the nominally Swedish town of Greifswald. In 1659 and 1678, Brandenburgian troops bombarded the town. The first bombardment hit mainly the northeast part of town, wrecking 16 houses. The second bombardment leveled 30 houses and damaged hundreds more all over the city. Cannonballs of this second bombardment can still be seen in the walls of St Mary's Church.

During the Great Northern War (1700–1721), Greifswald was compelled to house soldiers. While besieging neighboring Stralsund, Russian tsar Peter the Great allied with George I of Great Britain in the Treaty of Greifswald. Large fires in 1713 and 1736 destroyed houses and other buildings, including City Hall. The Swedish government had issued decrees in 1669 and 1689 absolving anyone of taxes who built or rebuilt a house. These decrees remained essentially in force, under Prussian administration, until 1824.

About 1900, the town – for the first time since the Middle Ages – expanded significantly beyond the old town walls. Also, a major railway connected Greifswald to Stralsund and Berlin; a local railway line further connected Greifswald to Wolgast.