Soest was one of the major cities in Westphalia during the 11th./12th century, having a population of around 10.000. Founded (like Erwitte and Paderborn to the east) on the ancient "Hellweg" (=Saltway), Soest played a major role within the Hanseatic League. Once it was even the capital of Westphalia - and (1531) a centre of Protestant Reformation in the area.

The town centre has more than 600 listed buildings and a couple of old churches. The "Patrokli Dom" was the church of the canonical foundation, which existed from the 10th century until its abolition in 1812. Since 1823 the church has been the parish church of the St. Patrokli parish.

The original building was completed before 1000. In the course of a further building phase the vaulted aisles were erected. At the same time, the transepts were expanded, the westwerk was rebuilt and an attached cloister were added to the south transept. The altar was consecrated in 1118.

Later the nave and the transepts were vaulted and the whole interior received painted decoration. This phase of construction ended with the reconsecration of the church by Cologne Archbishop Rainald of Dassel in 1166.

The romanesque crypt, destroyed (blown up!) after the secularisation (to have an even floor in the nave), was reconstructed after WWII, when the church got "rebuilt", after severe damages due to bombs, that had hit the church.