The Sword-singers (or Ansei) were a group of expert Redguard warriors from Yokuda and, for a while, Hammerfell.
The origins of the singers lie in a group of desert artisans, originally recruited from among the offspring of high Yokudan families. They built a temple to the gods of war and a training hall named "The Hall of the Virtues of War" in which they could practice their combat skills and the art of forging powerful swords. In 1E 617, the emperor Randic Torn started a divide between the singers and the common people by restricting the wearing of swords to the singers.
Men joining the group were known as "Brothers of the Blade" and women as "Maidens of the Spirit Sword". Two sources suggest that new members were recruited into the order at age eleven, but is unclear whether all recruits joined at this age. Certainly, one of the most celebrated singers, Frandar Hunding, was so skilled in swordsmanship by age 14 that he could use his abilities to provide for his mother and four brothers.
The greatest of the sword-singers were known as Ansei, or "Saints of the Sword" and formed their own training schools to pass on their skills. To become an Ansei of the first rank, a sword-singer had to demonstrate an ability to form the Shehai, a sword formed out of the singer's own spirit. Higher ranks were also possible. The study of the Shehai was known as "Shehai Shen She Ru", the Way of the Spirit Sword. When formed by a high-level Ansei, the Shehai was "an unstoppable weapon of great might" and made the singer capable of astonishing feats of swordsmanship.
In around 1E 780, the Yokudan Emperor Hira became afraid of the threat he perceived from the singers and launched a campaign to wipe them out. Frandar Hunding devised a strategy he called the "Hammer and Anvil", and eventually won a decisive victory against the emperor at the foot of Hattu Mountain. The war made the singers aware that they were no longer welcome in the land, and they set sail from the port of Arch, eventually arriving in the land they named Hammerfell.
By the 2nd century of the Third Era, the Way of the Sword was still being studied but many of the ancient secrets had been almost lost, with even the most venerable masters only capable of forming insubstantial Shehai. The ways of the Ansei are still admired by other warriors.