In 1218, an artilleryman known only by his first name, Nicholas, received 39 livres from Blanche of Navarre, countess of Champagne, whom he had served during her struggles to maintain the county of Champagne for her under-age son, Count Thibaut IV. Both the payment and its purpose – to compensate Nicholas for the loss of his equipment as well as to help him defray the costs incurred during the return to his home land – reveal his status as a mercenary. The same financial account also records a payment made for sending an army out for twenty-seven days, as well as payments of ten livres to fortify her castle at Provins with ditches and thirty-two solidi to repair them. This financial account, offering only incomplete fragments of Blanche’s extraordinary expenses from 1217 to 1219, demonstrates two key components of thirteenth-century warfare: the use of money and the necessity of good administration for a successful outcome in war. Despite scholarship claiming that women disappeared from warfare in the thirteenth century, Blanche was clearly as immersed in the business of war as her male counterparts.

These components of warfare – money and administration – were not new in the thirteenth century. As Philippe Contamine has noted, money came into regular use for military matters around 1150, and by 1200 soldiers, even vassals, could expect to receive pay, while rulers accepted monetary payments in lieu of armed service (as did Philip Augustus in 1202–4). Pure feudo-vassalic ties, in which a lord granted a landed fief in exchange for military service, faded during the thirteenth century, retainer contracts were in use by the end of the century, and fief rentes (fiefs of regular monetary payments instead of a grant of land) were standard practice. Thus, vassals did not disappear and indeed remained the prominent part of thirteenth-century armies, albeit with monetary incentives.

Furthermore, as John Gillingham argued when discussing the quintessential medieval general Richard Lionheart, medieval warfare required careful and methodical planning. In fact, Gillingham asserted that Richard’s success on the battlefield, while helped by his personal prowess and charisma, owed a great deal to his skills as an administrator.