His predecessor, Ataulf, had been mortally wounded in his stables at the palace of Barcelona by an assassin.
The assassin was probably a loyal servant of Sarus, a Gothic noble and personal enemy whom Ataulf had earlier slain.
He also forced Galla Placidia, widow to Ataulf and daughter of Roman Emperor Theodosius I and sister to Emperor Honorius to walk more than twelve miles on foot among the crowd of captives driven ahead of the mounted Sigeric.
On the seventh day after his accession, Sigeric was assassinated and replaced him with Ataulf's relative, Wallia.
Due to this, as well as to the fact that his reign was a usurpation, and brief, Sigeric does not appear on some Visigothic king lists.