In the Middle Ages, Meinersen was the seat of the "Meinersen family", who were first mentioned in 1147. They received their dominions directly as imperial fiefs and were not subordinate to any prince or duke. From 1248 to 1260, Oda von Meinersen was the abbess of the combined Gernrode and Frose monasteries. In 1292, troops of the Duke of Brunswick conquered the moated castle of Meinersen, which stood on the Weinberg district east of the Oker. In 1316, Duke Otto the "Strict of Lüneburg" destroyed the castle and added Meinersen to the principality of Lüneburg. Around 1350 a castle was built on the west side of the 0ker. During the HiIdesheim collegiate feud (1518-23) there was severe damage, but as a Merian engraving from 1654 shows, the palace complex was restored. In its place, the office building, todays artists house (Künstlerhaus), was built in 1765. The family von Meinersen  died out in 1367 with the death of Bernhard II. In 1428 Meinersen reverted to the Duchy of Brunswick and was then loaned or pledged to various owners. In 1532 the duchy set up the Meinersen office, which existed until 1885 and collected taxes from the residents.