Sywardus

In the twelfth-century Danish history Gesta Danorum (The Deeds of the Danes), Siward, (Sywardus), was an ancient king in Götaland, who had a daughter named Alfhild, who became a legendary Viking pirate.

To protect his daughter from unworthy suitors, Siward had her chamber guarded by a lizard and a snake.

When Alf, a Danish prince, managed to defeat the animal guards, Siward told him that he would only accept "that man for his daughter's husband, of whom she made a free and decided choice".

At first, Alfhild said no and ran away from home, but, after some adventures with her Viking fleet, she met Alf in a sea combat, and, after losing the battle, decided to marry him.

[1] In the original Latin text of Gesta Danorum, it is rendered Siwardus and Sywardus.