According to Norse mythology, Odin obtained the runes of wisdom by impaling himself on a spear for nine days and nights after plucking out his right eye. He essentially sacrificed himself to himself to get the runes of wisdom. According to legend, he showed the runes to the Valkyries to make them wise.
The Norse people adopted their 24-letter alphabet of runes, and credited Odin with creating the runes. No one is exactly sure when the runes began to be used by the Norse people. Some scholars have suggested that these runes existed as early as 1500 BC, while others believe that they were not used until 800 AD.
Despite the disagreements over the time these runes were created, historians are much more certain of their function. Each rune had a name, a phonetic sound, and more importantly, a deeper meaning. For example, a rune could be used as a sound to construct another word, or it could stand on its own and mean "courage." Runes were not just a means of communication; they were sacred.
There were important ceremonies that the Norse people performed in which they would write a rune on a rock or stick. They would write a symbol for courage, luck, longevity, success in battle, a happy marriage, or numerous other things. The belief was that the runes needed to be written in blood, and for the charm to be even more powerful, the rune needed to be written with the blood of a pregnant woman.