Taxes
Despite all of this, England's government could function without a strong king. The efficient civil service, established by the powerful King Henry II had run England throughout the reign of Richard I. But the government needed money, for during this period of prosperity mercenary soldiers cost nearly twice as much as before. The loss of the French territories, especially Normandy, greatly reduced the state income and a huge tax would have to be raised in order to attempt to reclaim these territories. Yet it was difficult to raise taxes due to the tradition of keeping them at the same level.
Novel forms of income included a Forest law, a set of regulations about the king’s forest which were easily broken and severely punished. John also increased the pre-existing scutage (feudal payment to an overlord replacing direct military service) eleven times in his seventeen years as king, as compared to eleven times in twice that period covering three monarchs before him. The last two of these increases were double the increase of their predecessors. He also imposed the first income tax which rose, what was at the time, the extortionate sum of £60,000.
http://en.wikipedia.org/wiki/Magna_C...of_Magna_Carta