Ammensleben Monastery can look back on more than 900 years of history. A church was founded in Groß Ammensleben by the Counts of Hillersleben around 1110. Ten years later, an Augustinian canons' monastery was added to it. This was converted into a Benedictine monastery just nine more years later. The monastery existed until it was dissolved until 1804.
As early as the first half of the 11th century, the ancestors of the Counts of Ammensleben owned some goods. The church was originally built in the Romanesque style. This created a basilica without a transept. Even in the present, this building of Romanesque origin still shapes the image of the church.
Once upon a time, four towers were supposed to adorn the building. However, a tower was only built to the northwest. While the country house in the Romanesque style has three aisles with eight bays, changes were made to the west building and choir at a later date. In 1170 an additional column portal including a two-part tympanum was built.
In 1334 a Lady Chapel was built. An Ursula chapel followed in the 15th century. The church, initially provided with a flat roof, was partially provided with a ribbed vault at the beginning of the 16th century. In the west this ended with two towers.
Ammensleben Monastery of St. Peter and Paul later survived the Reformation as a Catholic institution. It was not until 1804 that the monastery was secularized.