Harald Fairhair in the context of "Christianity in Iceland"

Olaf Tryggvason (960s – 9 September 1000) was King of Norway from 995 to 1000. He was the son of Tryggvi Olafsson, king of Viken (Vingulmark, and Rånrike), and, according to later sagas, the great-grandson of Harald Fairhair, first King of Norway. He is numbered as Olaf I.

Olaf was important in the conversion of the Norse to Christianity, but he did so forcibly within his own kingdom. He is said to have built the first Christian church in Norway in 995, and to have founded the city of Trondheim in 997. A statue dedicated to him is located in the city's central plaza.

The monarchy of Norway is the system used in Norway by which a hereditary monarch reigns as head of state under a constitutional monarchy with a parliamentary system. The Norwegian monarchy can trace its line back to the reign of Harald Fairhair and the previous petty kingdoms which were united to form Norway; it has been in unions with both Sweden and Denmark for long periods.

The present monarch is King Harald V, who has reigned since 17 January 1991, succeeding his father, Olav V. The heir apparent is his only son, Crown Prince Haakon. The crown prince undertakes various public ceremonial functions, as does the king's wife, Queen Sonja. The crown prince also acts as regent in the king's absence. There are several other members of the royal family, including the king's daughter, grandchildren and sister. Since the dissolution of the union between Norway and Sweden and the subsequent election of a Danish prince as King Haakon VII in 1905, the reigning royal house of Norway has been a branch of the Schleswig-Holstein-Sonderburg-Glücksburg branch of the House of Oldenburg; originally from modern-day Schleswig-Holstein in Germany, agnatically (through Prince Philip) the same royal house as the British (since the accession of Charles III), Danish and former Greek royal families.

The list of monarchs of Norway (Norwegian: kongerekken or kongerekka) begins in 872: the traditional dating of the Battle of Hafrsfjord, after which victorious King Harald Fairhair merged several petty kingdoms into that of his father. Named after the homonymous geographical region, Harald's realm was later to be known as the Kingdom of Norway.

Traditionally established in 872 and existing continuously for over 1,100 years, the Kingdom of Norway is one of the oldest states of Europe: King Harald V, who has reigned since 1991, is the 64th monarch according to the official list. During interregna, Norway has been ruled by variously titled regents.

Ynglingatal or Ynglinga tal (Old Norse: 'Enumeration of the Ynglingar') is a Skaldic poem cited by Snorri Sturluson in the Ynglinga saga, the first saga of Snorri's Heimskringla. Þjóðólfr of Hvinir (Thjodolf), who was a poet for Harald Fairhair (r. 872–930), is traditionally credited with its authorship. Snorri quotes frequently from this poem and cites it as one of the sources of the saga. The composition of the poem is dated to the 9th century.

The poem lists the partly mythical and partly historical ancient Swedish kings; twenty-seven of whom are mentioned in the poem, along with details about their deaths and burial places. The title Ynglingatal alludes to Yngling, who had the name Yngve-Frey—another name for Frey, the god who was worshipped in Sweden. Yngling allegedly descended from Frey's son Fjölnir. Snorri portrayed Harald Fairhair as a descendant of the Ynglings. The poem was written on behalf of Ragnvald Heidumhære, a cousin of King Harald Fairhair, and its last stanza is about Ragnvald.

Heimskringla (Icelandic pronunciation: [ˈheimsˌkʰriŋla]) is the best known of the Old Norwegian kings' sagas. It was written in Old Norse in Iceland. While authorship of Heimskringla is nowhere attributed, some scholars assume it is written by the Icelandic knight, poet and historian, Snorri Sturluson (1178/79–1241) c. 1230. The title Heimskringla was first used in the 17th century, derived from the first two words of one of the manuscripts (kringla heimsins, "the circle of the world").

Heimskringla is a collection of sagas about Swedish and Norwegian kings, beginning with the saga of the legendary Swedish-Norwegian dynasty of the Ynglings, followed by accounts of historical Norwegian rulers from Harald Fairhair of the 9th century up to the death of the pretender Eystein Meyla in 1177.