l'Isle-Jourdain

The lords of L'Isle-Jourdain were Gascon vassals of the counts of Toulouse, holding a Save-river lordship west of Toulouse that grew by purchase and conquest from the early eleventh century. The line is traced from Odon Raymond around 1000, and generations of its lords bore the name Jourdain.

Jourdain III married Esclarmonde of Foix in the late twelfth century, and Bernard IV Jourdain, ruling from about 1303 to 1340, married a daughter of the counts of Foix, tying the house to the south's greatest families. In 1337 the family still held the ancestral lordship, which was raised to a county in 1340 under Bertrand I.

The line ran to Jourdain VI, the last count; ruined and heirless, he sold the county in 1404 to the lord of Clermont, later duke of Bourbon, who resold it in 1421 to John IV of Armagnac. With that sale the house came to an end.