There is no more intriguing example of the use of the English royal treasure as a war chest than the financing of the 1415 expedition which led to the battle of Agincourt. A royal treasure embodied magnificence and served as an arm of diplomacy, but it was also a bank. In times of war and of other pressing need, English kings, like other European rulers, had of course often resorted to raising loans by pledging jewels and plate to corporations, syndicates and wealthy individuals. They would continue to do so until well into the modern period. The arrangements made by Henry V in 1415 seem, however, to be unique. For the first and probably the only time, as well as raising funds by pledging valuables to non-combatants, jewels and plate were pledged directly to the captains indenting for war service to guarantee the second quarters' wages for themselves and their retinues.

A mass of records surrounding the pledging and recovery of these valuables has survived in the National Archives at Kew, in the British Library and elsewhere. The background and administration of the Agincourt campaign, married to a wider political, military and economic context, have been well studied, but the nature and function of the valuables themselves demand closer attention. The surviving documentation is copious, although far from complete. It consists of about 135 so-called jewel indentures, a few being duplicates, as well as the surviving particular accounts of some captains, a single enrolled account and scattered exchequer records surrounding the closure of certain captains' accounts.