In the rush to lavish attention on the reforms of royal government enshrined in the Provisions of Oxford and Westminster, it is perhaps understandable that scholarly focus has not been directed to ways in which the root cause of the initial crisis was tackled – money, or rather the crown's acute lack of it. Various factors combined to trigger the ‘palace coup’ in April 1258, but all had a financial origin. King Henry III's promise to pay the papacy 135,541 marks in 1254 to secure the Sicilian crown for his younger son Edmund had triggered a meltdown of the royal finances, which were already strained by the outlay required to pacify Gascony in 1253–54. Although David Carpenter has suggested that Henry's regime was not bankrupt, given the amount of gold he was amassing in preparation for the Sicilian campaign, the king was particularly hard-pressed by his creditors and was struggling to raise sufficient money to pay them off – in short, he was suffering a cash liquidity crisis. The situation was exacerbated by the perception that access to royal patronage was restricted to a closed circle – primarily Henry's Lusignan family, who continued to profit during this time of financial hardship at the expense of others. Under threat of excommunication from Pope Alexander IV, and with another military campaign against the Welsh looming on the horizon that Henry could ill afford, the atmosphere at court was already tense when the king made an ill-judged request for more money in April 1258 – specifically, in the hope of resurrecting his Sicilian plans. This proved to be the final straw for many of Henry's beleaguered magnates, and the leading conspirators used the crown's financial weakness as the pretext for their own demands for root-and-branch reform of central government and measures to tackle the corruption of its various officials in the shires.

The causal links between fiscal crisis and structural reform are well rehearsed, with recent historians such as Carpenter, Richard Cassidy, James Collingwood, Adrian Jobson and Benjamin Wild building on the classic works of Mabel Mills, T.F. Tout, R.F. Treharne and I.J. Sanders to examine specific aspects of Henry III's financial administration and the levels of revenue at his command.