The settlement arose in the Eastphalian Salzgau region of the medieval Duchy of Saxony; the Immedinger relatives of duchess consort Matilda, wife of Henry the Fowler, founded a nunnery here as a proprietary monastery about 940.

During the Thirty Years' War, Imperial and Catholic troops tried to reconquer the former Hildesheim estates and defeated a Protestant army under King Christian IV of Denmark at the nearby Battle of Lutter in 1626.

In 1803 the prince-bishopric was securalised to the Electorate of Hanover and Feldzeugmeister Count Friedrich von der Decken acquired the former monastery as his residence in 1817.

The large park (Schlosspark) with a serpentine lake in the English landscape garden manner was laid out in 1847 for Count Adolf von der Decken.

Ringelheim has some shopping facilities (supermarket, drug-store, retail), restaurants, banks, doctor, dentist, pharmacy, an alcohol detox clinic and an institution for handicapped persons.