The god of war.
Tyr was regarded also as the god of courage and of war, and therefore frequently invoked by the various nations of the North, who cried to him as well as to Odin to obtain victory. That he ranked next to Odin and Thor is proved by his name, Tiu, having been given to one of the days of the week, Tiu’s day, which in modern English has become Tuesday. Under the name of Ziu, Tyr was the principal divinity of the Suabians, who originally called their capital, the modern Augsburg, Ziusburg. This people, venerating the god as they did, were wont to worship him under the emblem of a sword, his distinctive attribute, and in his honor held great sword dances, where various figures were carried out. Sometimes the participants forming two long lines, crossed their swords, point upwards, and challenged the boldest among their number to take a flying leap over them. At other times the warriors joined their sword points closely together in the shape of a rose or wheel, and when this figure was complete invited their chief to stand on the navel thus formed of flat, shining steel blades, and then they bore him upon it through the camp in triumph. The sword point was further considered so sacred that it became customary to register oaths upon it.
“... Come hither, gentlemen,
And lay your hands again upon my sword;
Never to speak of this that you have heard,
Swear by my sword.”
Hamlet (Shakespeare).
A distinctive feature of the worship of this god among the Franks and some other Northern nations was that the priests called Druids or Godi offered up human sacrifices upon his altars, generally cutting the bloody or spread eagle upon their victims, that is to say, making a deep incision on either side of the backbone, turning the ribs thus loosened inside out, and tearing out the viscera through the opening thus made. Of course only prisoners of war were treated thus, and it was considered a point of honor with north European races to endure this torture without a moan. These sacrifices were made upon rude stone altars called dolmens, which can still be seen in Northern Europe. As Tyr was considered the patron god of the sword, it was deemed indispensable to engrave the sign or rune representing him upon the blade of every sword—an observance which the Edda enjoined upon all those who were desirous of obtaining victory.
“Sig-runes thou must know,
If victory (sigr) thou wilt have,