In Norse lore, the god, Odin, impaled his heart with his own spear and hung on the world tree, Yggdrasil, for nine days and nights all to perceive the meaning of the runes.  

The runes were symbols that sprang from the Well of Urd – the source of fate – and the Norns used these runes to carry that fate up the trunk and branches of Yggdrasil to the nine worlds amidst its boughs. 

Odin made his sacrifice at great anguish and risk to himself because he knew that the runes conveyed deep meaning, and if he could understand their meaning he would gain profound wisdom and power.So we see from this story how the Vikings thought of runes not merely as letters but as having potent virtues within themselves of a metaphysical or even magical nature.  

The Norse and other Germanic peoples wrote with runes since at least the first century.  However, they did not use this writing the way we do now, or even the way Mediterranean and other neighboring cultures did then.  Instead, runes were for inscriptions of great importance.  They could be carved into rune stones to commemorate ancestors and mark the graves of heroes.  Because they had inherent meaning, they could be used as a means of communication between the natural and supernatural, and could thus be used as spells for protection or success.