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 Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.