In Scandinavian mythology the goddess Skaði wanted to avenge her father (originally husband), who had been killed by the gods. They agreed to give her a (new) husband as compensation. She wanted to marry the most beautiful god, Baldr, but she had to choose a husband just by looking at their feet. She found a pair, which she believed to be Baldr's, but which turned out to be Njörðr's. At first glance this does not support my theory that the queens were elected because of their beauty, because in this myth we see a god being chosen by a goddess because of his beauty. However, this is only due to the fact that the myths were changed some time in the Iron Age, when the Scandinavian society went from matriarchy to patriarchy. It was originally a god who chose his wife because of her beautiful feet. Skaði was namely the name of a god and Njörðr the name of a goddess, known from the Bronze- and early Iron Age as the god Skanþan and the goddess Nerþuz respectively.
Although the society was matriarchal it was still ruled by kings. The right to rule was tied to the queen. In order to become king and to rule the men had to marry the queen. They wanted an able king though, so to make sure they found the man best suited they arranged different types of contests. We know this best from Ancient Greece as the Olympic games, being one of the four Greek yearly contests with this purpose. In short; the winner of the beauty contest married the winner of the “sports” contests, and together they ruled the society.
In order to keep their titles and power they had to win new contests, every single year, and naturally they would eventually fail; the women grew old and lost their beauty, the men grew old and lost their strength. This system made sure the queen was always the most healthy (beautiful) woman, and the king the strongest and most skilled man of them all. This system also meant that if the queen kept her title, but her husband did not, she would marry another man instead, next year, or the other way around.
Not everyone could participate in these contests. To be allowed access to the arena in Scandinavia the challengers had to make the king vulnerable to them. The king was a god, a solar deity, and because the life force of the Sun was hidden away in the oak, and the life force of the oak in the mistletoe, all men who wished to challenge the king had to bring their own mistletoe, as a key to the arena. Without it they were not allowed to challenge the king. Elsewhere in Europe, they used other plants, like the laurel branch in Ancient Greece, but the principle was the same; they had to bring an evergreen bough from a sacred tree to win the right to challenge the king and compete for kingship.
We can therefore now understand why a myth tells us that Baldr was invulnerable to all attacks, except the one from Höðr (“hood”), who brought the mistletoe to the arena. For obvious reasons, he had received this key from Loki (“lightning”), the power that had brought it from the sky to the oak tree, where Höðr, the hooded sorcerer, found it.
We know that the challengers needed a key, the golden bough, to gain access to the arena, but we also know that he needed other keys. The king was not only a solar deity, but also represented every other male deity. From the Norwegian fairy tale Prinsessen som ikke kunne målbindes (“The Princess who could not be put to Silence”), where the main character, Askeladden (“Ash-limp”), was able to make the princess silent (and by doing so gain the right to marry her and inherit the kingdom) because he was the only bailer who had brought with him all the necessary “keys” to make the king vulnerable; he brought a dead magpie, representing the life force of Skanþan/Skaði; he brought a wicker buckle, representing the life force of Þunaz/Þórr, taken from Meginjörð (“Earth force”), his belt of strength; he brought a broken plate, representing the life force of the solar deity, Balþuz/Baldr, the broken Sun disc; be brought a worn out shoe, the life force of the forest deity Wídanaz/Víðarr, his one shoe, used to kill the wolf in Ragnarök; he brought a pair of goat horns, representing the life force of the fertility deity Fraujaz/Freyr, in ancient times portrayed as a horned god; he brought a wedge, representing the life force of Lukan/Loki, the lightning striking and breaking rocks. The queen in these fairy tales is often described as a princess, because in the Christian era, when these already politically incorrect fairy tales were told in secret, one could not comprehend how or tolerate that a queen who was already married to a king could divorce him and get married again, to the king's challenger.
A good king had to be skilled too; he had to know how to make fire, catch fish, find fresh and clean water, tame horses, gather honey and do other things that would make him a good king. Both French and German fairy tales, like those collected and published by the Grimm brothers, as well as Norwegian ones collected and published by Asbjørnsen and Moe, are full of examples of competitions where the hero needs to show his skills. In addition to that, the challengers competed in races, they hurled rocks, threw spears and axes, swam, shot with bow and arrow or slings, ate and drank, rode horses and played different ring-games (known today as knight's games), jumped and wrestled, or participated in other competitions. In most of Europe these competitions degenerated into pure entertainment, carnivals and knight tournaments when Christianity arrived, and in Scandinavia and parts of Eastern Europe, that were Christianised much later than the rest of Europe, they turned into innocent fun and traditional games for children.
The men did not only compete in physical games. They had to create the finest, funniest or cleverest poems and challenged each other in different word games. Physical strength was not enough to become king. A healthy, quick and alert mind was no less important.
If these competitions ended in a draw the two best men had to meet in a final wrestling contest, to determine who was the worthy winner. Some kings ruled for many years, but naturally they were all replaced sooner or later, by younger and stronger men.
The king, whether he was newly appointed or had his title renewed, had to make a promise to do something spectacular within one year of his crowning. This promise is known in Scandinavia as a brageløfte (“winner's promise”). The king swore his oath, and with all his force cut a wooden idol with his sword. The scar in the idol would remind everybody of his promise, and if the sword got stuck in the idol and he could not get it out he lost his title. The challenger with the second best record would then be allowed to pull out the sword, and if he succeeded he would become king instead. If he did he had to fulfil the oath given by the person who placed the sword there, though. If he too failed, the next one in line could try, and so forth, until one of them finally succeeded and became king. We know this tradition vaguely from the British myth about king Arthur, who became king of Britain after managing to pull the king's sword from a stone. Arthur then had to free his kingdom, Albion, from enemy occupation, as promised by the original king when he cut the stone with his sword.
In the age of sorcery the old king himself was killed by the new, with a sword, when he took his place. This was necessary because the old king was the ruler of the world, and for his life force and power to be transferred to the new king he first had to be killed. This was replaced in the age of gods by the symbolic death of the deity when the king slashed the idol with his sword. The deity was sacrificed and his powers transferred to the new king.