Norway's unification is traditionally dated to 872 CE, when Harald Fairhair (Harald Hårfagre) won the Battle of Hafrsfjord and declared himself king of a united Norway.
Continuous sovereign statehood: 1905–present (119 years). Continuous named kingdom: 872–present (1,152 years).
Norway celebrates Constitution Day (17 May) as its national day—commemorating the 1814 Eidsvoll Constitution, Europe's second-oldest written constitution still in force.