Olsok (literally "St.Olaf's Wake") is a name for July 29, traditionally the date for the Battle of Stiklestad in 1030, and the death of St. Olaf. He is remembered as the eternal king of Norway due to his attempts to (forcefully) convert the country to Christianity, and his martyrdom became an important tool for the Church.

In the Faroe Islands it is called Ólavsøka, and is an official holiday; in Denmark it is called Olai. The date is celebrated in various ways. In Norway it is an official flag day, and was for centuries the most important holiday. It is still reckoned as a second national day.

See also

• Olavsfestival
• Ólavsøka