St. Nicholas Cathedral is a Gothic church established in circa 1247. When the burghers of Elbing (Elbląg) first attempted to adopt the Protestant Reformation in 1525, the provost of St. Nicholas Church maintained Catholic practice. Since 1539 the city council tacitly tolerated and gradually openly promoted Lutheranism, so that St. Nicholas Church had become a Lutheran church by 1573.
Following King Sigismund III's Prussian regency contract (1605) with Joachim Frederick of Brandenburg and his Prussian enfeoffment contract (Treaty of Warsaw, 1611) with John Sigismund of Brandenburg these two rulers of Ducal Prussia guaranteed free practice of Catholic religion in prevailingly Lutheran Prussia. Based on these contracts Prince-Bishop Szymon Rudnicki of Ermland/Warmia achieved the restitution of St. Nicholas as Roman Catholic parish church in 1612, then the only one in Elbing, and remaining a Catholic church since.
St. Nicholas was damaged by fire in the late 18th century, then destroyed in World War II and reconstructed. In 1992, the building was elevated to the status of cathedral.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.