After declaring independence from Great Britain, the thirteen American colonies adopted new constitutions for themselves and for the union that bound them together. The U.S. Constitution, which in 1787 proposed the federal government in the form known in the modern era, was in fact the second national constitution; the Articles of Confederation, enacted in 1781 as the first national constitution, provided for a weak central government that was little more than a league of friendship. A small group of nationalists had wanted a more powerful central government, but their efforts in the drafting of the articles had failed, as did their efforts to amend them and to give the Congress of the Confederation additional powers. When a postwar depression created political turmoil, social unrest, and violence, leading political figures throughout the country grew worried and agreed to amend the Articles of Confederation by means of a general convention of the states.