The Senate was formed for a reason. It came after the HofR existed. The Senate was formed so that each state had 2 Senators, or in other words, equal representation and a counterbalance to the House Of Representatives which is heavily slanted toward states with higher population density.
Well, no.
Both the US House of Representative and the US Senate were hammered out at the Constitutional Convention at Philadelphia. The was the Sherman Compromise, which got the large and small States to agree...
The two Houses of Congress came into existance at the same time, neither was "first"...
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