Complex sentence: One of the reasons is said to be persisting heathen beliefs in the area, possibly concerning the pagan sacrifices at Trollkyrka, and the bishopry couldn't accept this and had the church destroyed.
Split into simpler sentences: One of the reasons is said to be persisting heathen beliefs in the area, possibly concerning the pagan sacrifices at Trollkyrka. The bishopry couldn't accept this and had the church destroyed.