The painting was commissioned by the Swedish reformer Olaus Petri, and the resulting controversies between him and King Gustav Vasa and the historical context remained a well-kept secret for centuries.

The stone and brick buildings are densely packed below the church and castle, which are rendered in a descriptive perspective (i.e., their size relates to their social status, rather than their actual dimensions).

[2] The wooden panel measures 163 by 110 centimetres (64 by 43 inches) and is composed of five vertical deals (softwood planks) reinforced by two horizontal dovetail battens.

The battens, together with the rough scrub planed back, have effectively reduced warping to a minimum and the artwork is well preserved, with only insignificant fissures and attacks by insects.

[3] A dendrochronological examination of the panel by doctor Peter Klein at the Institute für Holzbiologie in Hamburg determined that it is made of pine deals (Pinus silvestris), the annual rings of which date from various periods ranging from the 1480s to around 1618.

Copies of Erhard Altdorfer's apocalyptic woodcuts may have been available in Stockholm through the German merchant Gorius Holste who lived by Järntorget square and who was a friend of both Petri and Martin Luther.

[9] Modern scholarship has convincingly identified Jacob Heinrich Elbfas (1600–1664), guild master from 1628 and court painter of Queen Maria Eleonora from 1634, as the artist responsible.

A dendrochronological investigation showed that the wood used for the panel came from trees cut down in the early 17th century: the painting in question must therefore be a copy and not the restored original.

Once these layers were removed, it was discovered that the original grey-blue sky had been repainted with broad strokes of a deep blue dye mixed with a fixing agent.

This cartouche displayed the message: The twentieth day in the month of April was seen in the sky over Stockholm such signs from almost seven to nine in the forenoon"in Latin, repeated in Swedish and German.

[12] In 1523, as the newly elected King of Sweden,[13] Gustav Vasa had to unify a kingdom which, unlike a modern nation-state, was composed of separate provinces not necessarily happy with his reign.

He also had to prepare for a potential Danish attack, and resist the influence of German states and merchants with an interest in reintroducing the hegemony of the Hanseatic League over the Baltic lands.

[15] Shortly after his coronation, Gustav Vasa heard of the reformatory sermons delivered by Olaus Petri in Strängnäs and called him to Stockholm to have him appointed councillor in 1524.

[2] While both the king and Petri were thus devoted to both establishing what was to become the Swedish state and the new religious doctrine, they were also involved in domestic struggle for power,[17] a situation fuelled by various enemies and Counter Reformation propaganda.

The primary historical source describing the events following the celestial phenomenon is the minutes of the proceedings from the king's legal process against the reformers Olaus Petri and Laurentius Andreae in 1539–1540.

The process was originally described in the chronicle of Gustav Vasa written by the clerk and historian Erik Jöransson Tegel [sv] in the early 17th century.

In response, Petri warned his followers that the lords and princes interpreted his sermons as rebellious and complained about the ease with which punishment and subversion were carried through, while restoring "what rightly and true is" was much harder.

The oldest report, dating from the 1590s, is a handwritten manuscript simply confirming the event, and a publication on meteorological phenomena published in 1608 described the halo in 1535 as "five suns surrounding the right one with its rings as still depicted in the painting hanging in the Great Church[23]".

Even this confused report was soon forgotten and in 1632 the halo display in the painting was described in a German leaflet as three beautiful rainbows, a ball, and an eel hanging in the sky over the Swedish capital day and night for four weeks in 1520, furthermore interpreted as a prophecy announcing the forthcoming liberation of Protestant Germany by "the Lion from the North" (i.e. King Gustavus Adolphus).

[29][30] For the restoration of the Gamla stan metro station in 1998 the artist Göran Dahl furnished the walls and floors with motifs from various medieval textiles and manuscripts, including the Överhogdal tapestries and the 14th-century Nobilis humilis (Magnushymnen) from the Orkney Islands.

In 1468–1496, during the reign of Sten Sture the Elder, its size was doubled – the chapels were transformed into aisles, while rounded windows and a taller roof allowed more light into the building.

In the painting to the right of the church the eastern wing is accurately depicted as under construction, the exposed roof trusses confirming the inconvenience experienced by the monarch.

For the construction of the towers and other defensive structures, the king used bricks from the monastery Klara kloster located just north of the city but absent in the painting.

[43] The two defensive towers of the southern city gate appearing in the left foreground, are known to be much older than the painting but their history remains poorly documented.

The outer tower (Yttre Söderport) was built on an artificial island in the strait and was rebuilt in front of an expected attack by King Christian II of Denmark in the late 1520s.

In Blodbadstavlan ("The Bloodbath Painting"), an image ten years older than Vädersolstavlan, it appears with a cone-shaped roof seriously damaged during the Danish assault.

Additions younger than the 1530s, such as the reinforcements ordered by Gustav Vasa during the 1540s, are missing in the painting but present in engravings from 1560 to 1580, which confirms Vädersolstavlan is a credible contemporary document.

The wooden defence structure built along the shore around 1650 is absent in the painting, but the double row of piles protecting the western harbour is present.

[59] The sun dogs or parhelia, in the painting erroneously pinned to the misinterpreted arcs of the circumscribed halo, are rather frequent optical phenomena which appear when sunlight is refracted by hexagonal ice crystals forming cirrus or cirrostratus clouds.

[64] The white spot on the lower left part of the parhelic circle, opposite to the Sun, should be an anthelion, a bright halo always located at the antisolar point.