Complex sentence: The estate was established by King Harald Fairhair, the first king of a united Norway, shortly after the Battle of Hafrsfjord in year 872 and was one of the five similar estates the king build along the Norwegian west coast.
Split into simpler sentences: The estate was established by King Harald Fairhair, the first king of a united Norway, shortly after the Battle of Hafrsfjord in the year 872. Avaldsnes was one of the five similar estates the king build along the Norwegian west coast.