First+United+States+Congress-Marcus+M.

The Congress of the United States was created by Article I, section 1, of the Constitution, adopted by the Constitutional Convention on September 17, 1787, providing that "All legislative Powers herein granted shall be vested in a Congress of the United States, which shall consist of a Senate and House of Representatives." The first Congress under the Constitution met on March 4, 1789, in the Federal Hall in New York City. The membership then consisted of 20 Senators and 59 Representatives.