Olaf Tryggvason was a Viking king who ruled Norway from 995 to 1000. He played a significant role in the Christianization of Norway and was known for his military campaigns and efforts to spread Christianity. He is also remembered for his involvement in the Battle of Svolder, where he suffered a major defeat. Overall, Olaf Tryggvason is a prominent figure in Norwegian history due to his impact on the country's religious and political landscape during the Viking Age.