Religious institutions often have a long history that dates back to the time when Christianity was introduced, and in Hannover Region this happened 1200 years ago.When the Saxon country was conquered by the Franconians, Christianity was an important means to establish the power of the new rulers.

Two dioceses were created, west of the River Leine the diocese of Minden, and Hildesheim on the other side. Monasteries and nunneries were founded and supported, as well as numerous parishes. A number of impressive ancient churches can be found in Hannover Region such as Idensen, Mandelsloh and Ronnenberg, as well as a monastery and a number of convents. The oldest nunnery was the Stift of Wunstorf, established in 871.

Others are Barsinghausen, Mariensee, Wennigsen and Wülfinghausen. They have been altered during the centuries, great changes came to them in the course of the Reformation, but most of them are still in use as protestant convents. The buildings are impressive witnesses of the past, and most old parish churches are nowadays the oldest preserved buildings in their villages.