She was a neighbour and contemporary of the trobairitz Almucs de Castelnau, with whom she shared the composition of a tenso.
She may have belonged to the family of the lords of Tournel, one of the eight baronies of Gévaudan, and the one in which Chapieu lay.
Since the family adopted the exclusive use of the Tournel surname around 1250, Iseut's floruit is sometimes placed between those dates.
There is a long razo (explanatory gloss) preceding the exchange of stanzas (coblas) between Iseut and Almucs.
It tells how Iseut begged Almucs to pardon Gigo (Gui), lord of Tournon (Tornon) in the Vivarais.