Varnhem is the location of the oldest known stone church in Sweden outside of Scania, erected in the 1040s at the latest. It is also the location of a Christiancemetery which was in use during the end of the ninth century.
The Cistercian Order established Varnhem Abbey around 1150, not far from the old church. A new abbey church was erected to replace the older church; the abbey church is still in use.
Varnhem and in particular its abbey has received additional attention in recent years due to it being the main location of The Knight Templar trilogy written by Jan Guillou, and subsequently filmed. Arn Magnusson, the hero character of the series is portrayed as living there.