Final answer:
The United States Constitutional Convention in 1787 concluded with compromises on the international slave trade and the drafting of the final Constitution, which then required ratification by at least nine states.
Step-by-step explanation:
The question pertains to the closing stages of the United States Constitutional Convention in 1787, specifically the process of forging a final agreement on the proposed Constitution, the contentious debates over the international slave trade, and the eventual ratification process by the states. During the Convention, contentious issues were handled by various committees, with some seeking to resolve the question of the international slave trade and others focused on finalizing the document's language.
The agreement reached was signed on September 17, 1787, but this was just the beginning of a struggle for a new Constitution that required ratification by popularly elected state conventions, with a requirement that at least nine states had to ratify the document for it to become effective.