At "Hethemere" were the estates acquired by the nobleman Herbold von Hedinghausen in 1146 through his wife from the Archbishop of Cologne. Hemmern has always belonged to the ancestral parish of Altenrüthen and in 1709 built the St. Anna Chapel, whose origin is surrounded by legend and which was replaced by a new building in 1959. The coat of arms of the village, which is about 20 years old, reminds of the noble family of the von Hemmern family, who lived there in the Middle Ages and belonged to the Rüthen burghers. The family was also called Karge, but died out already in the 15th century.
The area of the village also includes the "Spitze Warte" to the southwest.
"Spitze Warte". This was originally the name for one of the 3 watchtowers on the eastern border of the medieval field of the town of Rüthen.
In 1856 a windmill was erected about 150 meters northeast of the original Warte, whose stone mill tower later received this name.