Marsan

The Viscounty of Marsan was a Gascon lordship centred on Mont-de-Marsan. Joined to the Foix-Béarn inheritance through Margaret of Moncade, it was held in 1337 by Gaston II of Foix-Béarn.

In 1380 Archambaud de Grailly married Isabelle of Foix and gained Marsan with her inheritance. The viscounty passed through the houses of Foix, Albret and Bourbon. Henry IV united Marsan with the French crown in 1607; in 1646 Louis XIV granted it with Armagnac to Henri of Lorraine.