the nation. The most pressing example was the way state legislatures responded to calls for economic relief. Many people were unable to pay taxes and debts due to a post-war economic depression that was exacerbated by a scarcity of gold and silver coins. States responded by issuing paper currency, which often depreciated in value, and by making it easier to defer tax and debt payments. These policies favored debtors at the expense of creditors, and it was proposed that Congress be given power to prevent such populist laws. When the government of Massachusetts refused to enact similar relief legislation, rural farmers resorted to violence in Shays' Rebellion (1786–1787). This rebellion was led by a former Revolutionary War captain, Daniel Shays, a small farmer with tax debts, who had never received payment for his service in the Continental Army. The rebellion took months for Massachusetts to put down, and some desired a federal army that would be able to put down such insurrections. These and other issues greatly worried many of the Founders that the Union as it existed up to that point was in danger of breaking apart. In September 1786, delegates from five states met at the Annapolis Convention and invited all states to a larger convention to be held in Philadelphia in 1787. The Confederation Congress later endorsed this convention "for the sole and express purpose of revising the Articles of Confederation". Rhode Island was the only state that refused to send delegates, though it would become the last state to ratify the Constitution, in May 1790. Operations and procedures Originally planned to begin on May 14, the convention had to be postponed when very few of the selected delegates were present on that day due to the difficulty of travel in the late 18th century. On May 14, only delegates from Virginia and Pennsylvania were present. It was not until May 25 that a quorum of seven states was secured and the convention could begin inside the Pennsylvania State House. New Hampshire delegates would not join the convention until July 23, more than halfway through the proceedings. Among the first things that the Convention did were to choose a presiding officer, unanimously electing George Washington to be the president of the convention. The Convention then adopted rules to govern its proceedings. Each state delegation received a single vote either for or against a proposal in accordance with