The crisis leading to the rebellion was precipitated by credit problems incurred following the American Revolutionary War, when many of the trade benefits of British colonialism vanished and British companies began to demand payment of debts. This debt ultimately trickled down to consumers, in large part small farmers. In addition the tax system at the time was highly regressive. As a result, many small farmers were forced to sell their land in order to meet their debts.
Initially the farmers' response was primarily political, a demand for the printing of fiat_money, which would cause inflation and therefore reduce the debt burden on the farmers. Other demands centered around demanding that debtor courts, which enforced many of the credit schemes at the time, be staffed by elected rather than appointed officials. These efforts were resisted and stymied by wealthy and influential parties, who had strong control of the government due to the property eligibility requirements for office at the time.
Initial disturbances centered mostly around freeing incarcerated farmers from debtor's prisons, but later escalated into efforts to shut down debtor courts. The lack of a standing army under the government of the time (set up by the Articles of Confederation) forced the elites to create a private army in order to quell what was becoming an increasingly radical rebellion.
The rebellion eventually gelled into an organized army, led by one Daniel Shays, a farmer and a former captain in the Revolutionary Army.
In 1787 the farmers, many of whom were former soldiers in the American Revolution, began plotting to attack the federal arsenal in Springfield, Massachusetts. An extended conflict between the rebels (of some 2000 men )and the opposing private army (of around 5400 men) followed, resulting in the rebels' eventual defeat.
Shays and his followers were defeated at Petersham, Massachusetts on February 3, 1787. Most were granted amnesty. Shays himself was sentenced to death for treason but pardoned by Massachusetts governor John Hancock. The breakup of this rebel army was followed by guerilla-style attacks on wealthy landowners, liberation of jailed farmers, arson and the like.
Shays' followers were banned from elected office for three years and were not allowed to serve on juries or vote. Eventually the force for the rebellion was dissipated both by an improving economy and by the election of sympathetic individuals to replace incumbents (including many of Shays' followers, despite the ban).
Later in 1787 twelve states sent delegates to a meeting in Philadelphia. Their purpose was to change the Articles of Confederation, but the subject changed to negotiations that were to lead to The United States Constitution. Fear of uprisings like Shays' Rebellion were a motivation for creating a strong central government, especially the creation of a standing federal army. In addition many states moved their capitals to rural regions, where state governments would be better informed of local events and better able to control such uprisings.
See also: Whiskey Rebellion