Julian Cesarini the Elder sent Observant Franciscans to Alsóváros, Szeged to protect Catholicism from Hussitism. They were given the St. Peter Church and hospital, built in the 13th century. The construction of the new church was led by friar Ianus, who also planned the late-gothic church of Kolozsvár and Nyírbátor.

The construction started around 1480. First, the nave and the northern and western part of the friary were built. The sanctuary, being also the choir, was built after this. As a result, the vaults are also different, having net-vault in the nave and stellar-vault in the sanctuary. The stones of the old St. Peter Church were built into the walls of the sanctuary and into the base of the bell tower. The year of the consecration is marked on two wall-mounted memorials. The bell tower was completed in 1730.

The church is one of the most spectacular examples of the Hungarian late-gothic architecture. Its superb, yet modest façade impresses the visitor. The nave is surrounded by 8 four-section pillars and the sanctuary is surrounded by 6 three-section pillars. The area of the church is 723 square meters. The inner length is 59.9 meters, the outdoor length is 63.5 meters. The height of the church is 20 m. The length of the nave is 36.6 m, the width is 13.2 m, the width of the sanctuary is 10,7 m.

The pilgrimage feast of the church is the day of Our Lady of the Snows, 5th August. The feast of Our Lady of the Snows is actually the denomination day of the Papal Basilica of Saint Mary Major, Rome. Pope Pius V inserted this feast into the General Roman Calendar in 1568. The legend of the feast: In the 4th century. During the pontificate of Liberius, the Roman patrician, John and his wife, who were without heirs, made a vow to donate their possessions to the Virgin Mary. The same night they had a vision of the Virgin Mary, who asked the couple to build a basilica in her honour on the very spot which was covered with snow the next morning, 5th August, on one of the hottest days of the year.