In 1979, King Olav V of Norway unveiled the monuments commemorating King Olav Tryggvason, King Olav II Haraldsson and Bishop Grimkjell. Olav Tryggvason is said to have celebrated the first mass at Moster in 995. At the Mostertinget council of 1024, King Olav II (later known as St. Olav) and Bishop Grimkjell introduced Christian canon law.
The monuments are placed just inside the church gates. The reliefs were designed by Johannes Mjeldheim and the carvings executed by Sverre Loge Pettersen.
<NB. Her er det foreslått å kutte detaljinformasjonen om sokneprestens initiativ, uthogging av granittblokken, og ikke minst striden med Riksantikvaren.>