The construction of the parish church in Morąg, of the size of the present nave, began in the years 1305-1312. In the 1440s, a chancel was added to the nave and a tower housing a sacristy in the ground floor. In the third quarter of the 14th century, the nave was enlarged. In 1414 the church survived the Morąg fire as the only building in the town. After 1505, master Matz from Gdańsk closed up the aisles with a diamond vault. Around 1550, wooden galleries were built in the aisles, demolished after the Second World War. In 1807, the chapel of the Mother of God was added from the south, and in 1856, during the renovation, the roof structure was replaced, as well as the door and window woodwork. In turn in 1895 in the nave, the flat boarded ceiling was pulled down and replaced with an apparent gypsum stellar vault. The first users of the temple were Catholics, after 1525 it was used by Evangelicals, and after the Second World War it became the property of Catholics again. In 1948, during the renovation, frescoes were discovered in the church and they were preserved.
The church is a pseudo-basilica, three-aisle and three-bay building, erected of bricks on a rectangular plan. Adjacent to the nave of the church is an octagonal chancel and a tower erected on a square plan, 35 meters high. The tower is topped with gables and a gable roof, although it was originally equipped with battlement. The side walls of the nave are reinforced with buttresses between which pointed windows were pierced. In the middle of the walls there is a cornice of profiled brick, and above, a plastered band. Inside, the aisles were separated from the central nave by four pillars and covered with diamond vaults. The presbytery features stellar vaults.
Due to its original shape and good condition, the parish church in Morąg is one of the most valuable buildings in the Elbląg diocese. A set of medieval figural paintings from the third quarter of the 15th century has survived on the walls of the chancel.
Rzempołuch A., Kościoły na Warmii, Mazurach i Powiślu, Olsztyn 1991.
Rzempołuch A., Przewodnik po zabytkach sztuki dawnych Prus Wschodnich, Olsztyn 1992.
Website leksykonkultury.ceik.eu, Kościół pw. św. Piotra i Pawła w Morągu.