who initiated this?
James Madison.
Constitutional Convention (United States)
James Madison of Virginia arrived in Philadelphia eleven days early and determined to set the 
what took place at the constitutional convention of 1787 The result of the convention was the creation of the Constitution of the United States. was slavery an important topic in it? Yes. was anything done to stop it? Congress would have the power to ban the international slave trade, but not for another twenty years. In exchange for this concession, the federal government's power to regulate foreign commerce would be strengthened by provisions that allowed for taxation of slave trades in the international market. what else did the convention include? Tthe delegates worked to define the powers of Congress. where in u.s did it happen ? July 17. which place or hall did it happen? The old Pennsylvania State House.
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Constitutional Convention (United States) [SEP] Madison's blueprint
James Madison of Virginia arrived in Philadelphia eleven days early and determined to set the convention's agenda. Before the convention, Madison studied republics and confederacies throughout history, such as ancient Greece and contemporary Switzerland. In April 1787, he drafted a document entitled "Vices of the Political System of the United States", which systematically evaluated the American political system and offered solutions for its weaknesses. Due to his advance preparation, Madison's blueprint for constitutional revision became the starting point for the convention's deliberations. Madison believed the solution to America's problems was to be found in a strong central government. Congress needed compulsory taxation authority as well as power to regulate foreign and interstate commerce.