Taken at its face value, the treaty of Toulouse may appear to be the testament of a Count of Foix who, having considered his own mortality, wished to put his earthly affairs in order. In 1389 Fébus had reached an advanced age, at least by medieval reckoning. Enough of his contemporaries, friends and foes alike, had failed to reach the threescore years and ten allotted by the Psalmist: the once mighty Edward, Prince of Wales and Aquitaine, dead at the age of forty-six; Charles V ‘the Wise’, at forty-four; the turbulent Louis d'Anjou, at forty-five. Dead also, the great champions: Chandos, Du Guesclin, both in harness; in a French prison, Fébus' cousin and comrade-in-arms, the famed Captal de Buch; and his brother-in-law Charles of Navarre, burned to death in his own bed; but then none closer and more tragic than the son slain by his own hand.

But while Fébus had ample cause to meditate on the uncertainty of life and death, he does not seem to have had the kind of premonition that prompts men to dictate their last will and testament. For the treaty of Toulouse was not a testament, either in form or in substance, but rather a contract whereby the Count of Foix mortgaged his entire estate to the French Crown in return for 100,000 francs and the lifetime grant of Bigorre. Like most contracts of that kind, it contained a clause providing for its reversal: in the event that Gaston III had ‘heir or heirs procreated and descended of [his] own body in true wedlock’, his entire estate, viz.