When you first think about women in mythology and folk tales, perhaps the role you think of is either the long-suffering mother or the damsel in distress. Women in real life and mythology were often used as rewards (think of Helen of Troy) or as currency for political alliances (such as Isolde being married to King Mark, despite her love for Tristan). But this was not always the case.
All Is Fair In Love And War
In older myths, women were often portrayed as powerful in and of themselves. They fought their own battles, rescued themselves and often ruled the known universe. Such powerful female mythological figures not only ruled over the aspects of war, but also love. Perhaps love and its dominating power over your life was seen to be just as devastating as battle.
Many Goddesses of love and war can be found in the mythologies of many cultures. They include the Babylonian Goddesses Ishtar (or Inanna), the Norse Goddess Freya (or Freja), and the Greek Goddess of love Aphrodite who winds up falling in love with Ares, the God of War.
In some myths, the Goddess is known far more for her destructive side than for her loving side. For example, the Hindu Goddess Kali is not only the destroyer of everything, she is also wife to Shiva, and a faithful wife as that. She is considered part of all Hindu Goddesses, including Goddesses known for love.
The Change In Female Protagonists
Along the way, the myths shifted from the Goddess being the warrior or active hero to her being a quieter source of power. In many cultures, in order to be considered the King, you had to bed the Queen, who was the living symbol of the land. This belief was still around at the time of Mary, Queen of Scots (1542 to 1587), (according to Mary, Queen of Scots by Antonia Fraser.
This is seen most dramatically in the myth of King Arthur and his Queen, Guinevere. She did not love King Arthur but Sir Lancelot, instead. But she would not leave Arthur, because to do so would be to make him less powerful and respected in the eyes of his subjects. Not only did King Arthur fail to produce any offspring that could carry on his line, he failed to be able to hold on to his kingdom, being killed in battle by Mordred, his own son by his half-sister or nephew, (depending on who you read).
Although women in mythology seemed at first glance to have to have lost their inherent power over the world, they were always the source from which all power sprung. The hero would not be able to perform great works without her help or favor. Whether overtly or covertly, women represent the currency of power in many mythologies around the world.