The office of Cofferer of the Wardrobe originated in the late 13th century when the Treasurer/Keeper's chief clerk took on particular responsibility for drafting the Wardrobe accounts. Working closely with the Treasurer, the Cofferer usually served as "locum tenens" when the Treasurer was otherwise engaged with affairs of state (as was often the case); thus the Cofferer came to be seen as, in effect, the working head of the Wardrobe, acting on the Treasurer's behalf. In his own right he oversaw a small accounting office, staffed by the 'clerks of the Cofferer', who went on to play a key role in the financial oversight of the Household; this was a precursor to the Board of Green Cloth).