At the constitutional convention of 1787 the great compromise between the large states and small states resulted in

The Great Compromise of 1787. Early in the Constitutional Convention, delegates envisioned a Congress consisting of only a single chamber with a certain number of representatives from each state. Each state is represented in Congress by two Senators and a variable number of members of the House of Representatives based on the state’s population as reported in the most recent decennial census. The process of fairly determining the number of members of the House from each state is called "apportionment."